Heterocyclic compound and organic light-emitting device including the same

ABSTRACT

An organic light-emitting device and a heterocyclic compound, the device including a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode and including an emission layer, wherein the emission layer includes a compound represented by Formula 1A or a compound represented by Formula 1B:

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2018-0024720, filed on Feb. 28, 2018,in the Korean Intellectual Property Office, and entitled: “HeterocyclicCompound and Organic Light-Emitting Device Including the Same,” isincorporated by reference herein in its entirety.

BACKGROUND 1. Field

Embodiments relate to a heterocyclic compound and an organiclight-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices (OLEDs) are self-emission devices that,as compared with other devices, have wide viewing angles, high contrastratios, short response times, and excellent characteristics in terms ofbrightness, driving voltage, and response speed, and produce full-colorimages.

The organic light-emitting device may include a first electrode on asubstrate, and a hole transport region, an emission layer, an electrontransport region, and a second electrode, which are sequentiallydisposed on the first electrode. Holes provided from the first electrodemay move toward the emission layer through the hole transport region,and electrons provided from the second electrode may move toward theemission layer through the electron transport region. Carriers, such asholes and electrons, recombine in the emission layer to produceexcitons. Then, the excitons are transitioned from an excited state to aground state, thereby generating light.

SUMMARY

The embodiments may be realized by providing an organic light-emittingdevice including a first electrode; a second electrode facing the firstelectrode; and an organic layer between the first electrode and thesecond electrode and including an emission layer, wherein the emissionlayer includes a compound represented by Formula 1A or a compoundrepresented by Formula 1B:

wherein, in Formulae 1A and 1B, ring A₁ is selected from a C₅-C₆₀carbocyclic group and a C₂-C₆₀ heterocyclic group, X₁ is S or Se, L₁ andL₂ are each independently selected from a substituted or unsubstitutedC₅-C₆₀ carbocyclic group and a substituted or unsubstituted C₂-C₆₀heterocyclic group, a1 and a2 are each independently an integer from 0to 5, when a1 is 2, 3, 4, or 5, the 2, 3, 4, or 5 L₁(s) are identical toor different from each other, and when a2 is 2, 3, 4, or 5, the 2, 3, 4,or 5 L₂(s) are identical to or different from each other, when a1 is 0,*-(L₁)_(a1)-*′ is a single bond, and when a2 is 0, *-(L₂)_(a2)-*′ is asingle bond, R₁ and R₂ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazino group, a hydrazonogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₂-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂),—P(═S)(Q₁)(Q₂), —S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂), at least one of R₁and R₂ is an electron donating group, b1 and b2 are each independentlyan integer from 1 to 10, when b1 is 2, 3, 4, 5, 6, 7, 8, 9, or 10, the2, 3, 4, 5, 6, 7, 8, 9, or 10 R₁(s) are identical to or different fromeach other, and when b2 is 2, 3, 4, 5, 6, 7, 8, 9, or 10, the 2, 3, 4,5, 6, 7, 8, 9, or 10 R₂(s) are identical to or different from eachother, c1 and c2 are each independently an integer from 1 to 10, atleast one substituent of the substituted C₅-C₆₀ carbocyclic group, thesubstituted C₂-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group,the substituted C₁-C₆₀ heteroaryl group, the substituted C₁-C₆₀heteroaryloxy group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group is selected from deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazino group, ahydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),—S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and —Si(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and—P(═O)(Q₃₁)(Q₃₂), Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group, and * and *′ each indicate abinding site to a neighboring atom.

The embodiments may be realized by providing a heterocyclic compoundrepresented by Formula 1A or Formula 1B:

wherein, in Formulae 1A and 1B, ring A₁ is selected from a C₅-C₆₀carbocyclic group and a C₂-C₆₀ heterocyclic group, X₁ is S or Se, L₁ andL₂ are each independently selected from a substituted or unsubstitutedC₅-C₆₀ carbocyclic group and a substituted or unsubstituted C₂-C₆₀heterocyclic group, a1 and a2 are each independently an integer from 0to 5, when a1 is 2, 3, 4, or 5, the 2, 3, 4, or 5 L₁(s) are identical toor different from each other, and when a2 is 2, 3, 4, or 5, the 2, 3, 4,or 5 L₂(s) are identical to or different from each other, when a1 is 0,*-(L₁)_(a1)-*′ is a single bond, and when a2 is 0, *-(L₂)_(a2)-*′ is asingle bond, R₁ and R₂ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazino group, a hydrazonogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₂-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂),—P(═S)(Q₁)(Q₂), —S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂), at least one of R₁and R₂ is an electron donating group, in Formula 1A,(R₁)_(b1)-(L₁)_(a1)-* and (R₂)_(b2)-(L₂)₂-* are not halogen, a phenoxygroup, a phenylthio group, an alkylthio group, or an alkoxy group, b1and b2 are each independently an integer from 1 to 10, when b1 is 2, 3,4, 5, 6, 7, 8, 9, or 10, the 2, 3, 4, 5, 6, 7, 8, 9, or 10 R₁(s) areidentical to or different from each other, and when b2 is 2, 3, 4, 5, 6,7, 8, 9, or 10, the 2, 3, 4, 5, 6, 7, 8, 9, or 10 R₂(s) are identical toor different from each other, c1 and c2 are each independently aninteger from 1 to 10, at least one substituent of the substituted C₅-C₆₀carbocyclic group, the substituted C₂-C₆₀ heterocyclic group, thesubstituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group,the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxygroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedC₁-C₆₀ heteroaryloxy group, the substituted monovalent non-aromaticcondensed polycyclic group, and the substituted monovalent non-aromaticcondensed heteropolycyclic group is selected from: deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinogroup, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂),—B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a biphenyl group, and aterphenyl group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),—S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and —Si(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and—P(═O)(Q₃₁)(Q₃₂), Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group, and * and *′ each indicate abinding site to a neighboring atom.

BRIEF DESCRIPTION OF THE DRAWINGS

Features will be apparent to those of skill in the art by describing indetail exemplary embodiments with reference to the attached drawings inwhich:

FIG. 1 illustrates a schematic view of an organic light-emitting deviceaccording to an embodiment;

FIG. 2 illustrates a schematic view of an organic light-emitting deviceaccording to an embodiment;

FIG. 3 illustrates a schematic view of an organic light-emitting deviceaccording to an embodiment; and

FIG. 4 illustrates a schematic view of an organic light-emitting deviceaccording to an embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawings; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art.

In the drawing figures, the dimensions of layers and regions may beexaggerated for clarity of illustration. It will also be understood thatwhen a layer or element is referred to as being “on” another layer orelement, it can be directly on the other layer or element, orintervening layers may also be present. Further, it will be understoodthat when a layer is referred to as being “under” another layer, it canbe directly under, and one or more intervening layers may also bepresent. In addition, it will also be understood that when a layer isreferred to as being “between” two layers, it can be the only layerbetween the two layers, or one or more intervening layers may also bepresent. Like reference numerals refer to like elements throughout.

As used herein, the terms “or” and “and/or” include any and allcombinations of one or more of the associated listed items. Expressionssuch as “at least one of,” when preceding a list of elements, modify theentire list of elements and do not modify the individual elements of thelist.

A heterocyclic compound may be represented by Formula 1A or 1B:

In Formula 1B, ring A₁ may be selected from or include, e.g., a C₅-C₆₀carbocyclic group and a C₂-C₆₀ heterocyclic group.

In an implementation, ring A₁ may be selected from or include, e.g., acyclohexadiene group, a dihydronaphthalene group, a dihydroanthracenegroup, a dihydrobenzoanthracene group, a dihydrophenanthrene group, adihydrobenzophenanthrene group, a dihydrotriphenylene group, adihydronaphthacene group, a dihydropyrene group, a dihydrochrysenegroup, a dihydropicene group, and a dihydrobenzopentaphene group.

In an implementation, ring A₁ may be a group of, e.g., one of thefollowing Formulae A₁₋₁ to A₁₋₁₂. For example, one of the followingFormulae A₁₋₁ to A₁₋₁₂ may share a C—C bond with the 5-membered ring ofFormula 1B

In Formulae 1A and 1B, X₁ may be, e.g., S or Se. In an implementation,X₁ may be S.

In Formulae 1A and 1B, L₁ and L₂ may each independently be selected fromor include, e.g., a substituted or unsubstituted C₅-C₆₀ carbocyclicgroup, and a substituted or unsubstituted C₂-C₆₀ heterocyclic group.

In an implementation, L₁ and L₂ may each independently be selected orinclude, e.g., a phenylene group, a pentalenylene group, an indenylenegroup, a naphthylene group, an azulenylene group, a heptalenylene group,an indacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, apyrrolylene group, a thiophenylene group, a furanylene group, animidazolylene group, a pyrazolylene group, a thiazolylene group, anisothiazolylene group, an oxazolylene group, an isooxazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an isoindolylene group, an indolylene group, anindazolylene group, a purinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a (quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a carbazolylene group, aphenanthridinylene group, an acridinylene group, a phenanthrolinylenegroup, a phenazinylene group, a benzoimidazolylene group, abenzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzooxazolylene group, anisobenzooxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup, a dibenzothiophenylene group, a benzocarbazolylene group, and adibenzocarbazolylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, apyrrolylene group, a thiophenylene group, a furanylene group, animidazolylene group, a pyrazolylene group, a thiazolylene group, anisothiazolylene group, an oxazolylene group, an isoxazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an isoindolylene group, an indolylene group, anindazolylene group, a purinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a carbazolylene group, aphenanthridinylene group, an acridinylene group, a phenanthrolinylenegroup, a phenazinylene group, a benzimidazolylene group, abenzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzoxazolylene group, anisobenzoxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup, a dibenzothiophenylene group, a benzocarbazolylene group, and adibenzocarbazolylene group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a pentalenyl group, an indenylgroup, a naphthyl group, an azulenyl group, a heptalenyl group, anindacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a naphthacenyl group, a picenyl group, a perylenyl group, apentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenylgroup, a coronenyl group, an ovalenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thiadiazolyl group, and animidazopyridinyl group.

In an implementation, L₁ to L₂ may each independently be or include,e.g., a phenylene group or a thiophenylene group.

In an implementation, L₁ and L₂ may each independently be selected fromor include, e.g., a group represented by one of the following Formulae3-1 to 3-22.

In Formulae 3-1 to 3-22,

Y₁ may be, e.g., O, S, C(Z₃)(Z₄), N(Z₅), or Si(Z₆)(Z₇),

Z₁ to Z₇ may each independently be selected from or include, e.g.,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group,a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, a silolyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an indolylgroup, an isoindolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aphthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, abenzosilolyl group, an isobenzothiazolyl group, a benzoxazolyl group, anisobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a dibenzosilolyl group, a carbazolyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, abenzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

Q₃₁ to Q₃₃ may each independently be selected from or include, e.g.,

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, a pyrazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, and a quinazolinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a pyrazinyl group, a quinolinylgroup, an isoquinolinyl group, a quinoxalinyl group, and a quinazolinylgroup, each substituted with at least one selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, and a phenyl group,

d2 may be, e.g., an integer from 0 to 2,

d3 may be, e.g., an integer from 0 to 3,

d4 may be, e.g., an integer from 0 to 4,

d5 may be, e.g., an integer from 0 to 5,

d6 may be, e.g., an integer from 0 to 6,

d8 may be, e.g., an integer from 0 to 8, and

* and *′ each indicate a binding site to a neighboring atom.

In Formulae 1A and 1B, a1 and a2 may each independently be, e.g., aninteger from 0 to 5. a1 indicates the number of L₁(s), wherein, when a1is 2, 3, 4, or 5, the 2, 3, 4, or 5 L₁(s) may be identical to ordifferent from each other. a2 may be described by referring to thedescription of a1.

When a1 is 0, *-(L₁)_(a1)-* may be a single bond, and when a2 is 0,*-(L₂)_(a2)-*′ may be a single bond.

In an implementation, a1 and a2 may each independently be, e.g., 0, 1,or 2.

In an implementation, in Formula 1A, at least one of a1 and a2 may notbe 0.

In Formulae 1A and 1B, R₁ and R₂ may each independently be selected fromor include, e.g., hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazino group, a hydrazono group, a substituted or unsubstitutedC₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group,a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₂-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₂-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryloxy group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₁)(Q₂)(Q₃),—B(Q₁)(Q₂), —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂), —P(═S)(Q₁)(Q₂),—S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂). In an implementation, at least oneselected from R₁ and R₂ may include an electron donating group.

Here, Q₁ to Q₃ are respectively defined the same as described above.

In an implementation, in Formula 1A, (R₁)_(b1)-(L₁)_(a1)-* may not be ahalogen, a phenoxy group, a phenylthio group, an alkylthio group, or analkoxy group and (R₂)_(b2)-(L₂)_(a2)-* may not be a halogen, a phenoxygroup, a phenylthio group, an alkylthio group, or an alkoxy group

In an implementation, R₁ and R₂ may each independently be selected fromor include, e.g.,

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, anda C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group,and a C₁-C₂₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amidino group,a hydrazino group, a hydrazono group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cycloctyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, a pyrimidinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and—P(═O)(Q₃₁)(Q₃₂);

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acycloctyl group, an adamantanyl group, a norbornanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a fluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, and an imidazopyrimidinyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acycloctyl group, an adamantanyl group, a norbornanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a fluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, and an imidazopyrimidinyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, aC₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cycloctyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁) and —P(═O)(Q₃₁)(Q₃₂); and

—N(Q₁)(Q₂), —B(Q₁)(Q₂), —P(Q₁)(Q₂), and —C(═O)(Q₁).

In an implementation, at least one selected from R₁ and R₂ may includean electron donating group.

Here, Q₁ to Q₃ and Q₃₁ to Q₃₃ are respectively defined the same asdescribed above.

In an implementation, R₁ and R₂ may each independently be selected fromor include, e.g.,

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, anda C₁-C₂₀ alkoxy group; and

a groups represented by one of the following Formulae 5-1 to 5-6.

In an implementation, at least one selected from R₁ and R₂ may includean electron donating group.

In Formulae 5-1 to 5-6,

K₁ may be selected from, e.g., *—C(R₂)(R₃₀)—*′, *—N(R₂₀)—*′, and*—Si(R₂₀)(R₃₀)—*′,

R₂₀, R₃₀, R₄₀, and R₅₀ may be defined the same as R₁ and R₂ of Formulae1A and 1B,

b₄₀ and b₅₀ may each independently be, e.g., an integer from 1 to 4, and

* indicates a binding site to a neighboring atom.

b1 and b2 in Formulae 1A and 1B may each independently be an integerfrom 1 to 10. When b1 is 2, 3, 4, 5, 6, 7, 8, 9, or 10, the 2, 3, 4, 5,6, 7, 8, 9, or 10 R₁(s) may be identical to or different from eachother, and when b2 is 2, 3, 4, 5, 6, 7, 8, 9, or 10, the 2, 3, 4, 5, 6,7, 8, 9, or 10 R₂(s) may be identical to or different from each other.

In an implementation, b1 and b2 may each independently be, e.g., 1 or 2.

c1 and c2 in Formula 1B may each independently be, e.g., an integer from1 to 10.

In an implementation, c1 and c2 may each independently be, e.g., 1 or 2.

In an implementation, the compound represented by Formula 1B may berepresented by, e.g., one of the following Formulae 1B-1 to 1B-4.

In Formulae 1B-1 to 1B-4, X₁ may be defined the same as in Formula 1B,L₁₁ and L₁₂ may be defined the same as L₁ and L₂ of Formula 1B, a11 anda12 may be defined the same as a1 and a2 of Formula 1B, and R₁₁ and R₁₂may be defined the same as R₁ and R₂ of Formula 1B.

In an implementation, the compound represented by Formula 1B may berepresented by, e.g., one of the following Formulae 1B-a to 1B-d.

In Formulae 1B-a to 1B-d, L₁₁ and L₁₂ may be defined the same as L₁ andL₂ of Formula 1B, a11 and a12 may be defined the same as a1 and a2 ofFormula 1B, and R₁₁ and R₁₂ may be defined the same as R₁ and R₂ ofFormula 1B.

In an implementation, the compound represented by Formula 1A or 1B maybe, e.g., one of the following Compounds 1 to 37.

The heterocyclic compound represented by Formula 1A or 1B may include anoxidized thiadiazole-based core. Light in an infrared ray (IR)wavelength range may be emitted by employing a molecular structureincluding a strong electron donating substituent (e.g., according toFormula 1A or Formula 1B), and the luminescent efficiency may beimproved by a thermally activated delayed fluorescent (TADF) mechanism.

An electronic device, e.g., an organic light-emitting device, whichincludes the heterocyclic compound, may have high external quantumefficiency may enable a long wavelength shift of a maximum emissionwavelength, the electronic device may be suitable for near infrared ray(NIR) emission, and may have a low driving voltage, high efficiency,high luminance, and a long lifespan.

A synthesis method of the heterocyclic compound represented by Formula1A or 1B may be recognized by those of ordinary skill in the art byreferring to Examples provided below.

At least one of the heterocyclic compounds represented by Formula 1A or1B may be used or included between a pair of electrodes of the organiclight-emitting device. For example, the heterocyclic compound may beincluded in a hole transport region, an electron transport region,and/or an emission layer. In an implementation, the heterocycliccompound represented by Formula 1A or 1B may be used as a material forforming a capping layer disposed outside the pair of electrodes of theorganic light-emitting device.

Another aspect provides an organic light-emitting device including: afirst electrode; a second electrode facing the first electrode; and anorganic layer between the first electrode and the second electrode andincluding an emission layer. In an implementation, the emission layermay include the heterocyclic compound represented by Formula 1A or 1B.

The expression “(an organic layer) includes at least one of theheterocyclic compound” may mean that “(an organic layer) may include oneheterocyclic compound belonging to the category of Formula 1A or 1B ortwo or more heterocyclic compounds belonging to the category of Formula1A or 1B.

For example, the organic layer may include only Compound 1 as theheterocyclic compound. In this regard, Compound 1 may exist only in theemission layer of the organic light-emitting device. In animplementation, the organic layer may include Compound 1 and Compound 2as the heterocyclic compound. In this case, the Compound 1 and Compound2 may exist in the same layer (for example, Compound 1 and Compound 2may exist in the emission layer), or may exist in different layers (forexample, Compound 1 may exist in the emission layer and Compound 2 mayexist in the electron transport layer).

In an implementation, the emission layer may include a host and adopant.

In an implementation, the dopant may include a compound represented byFormula 1A or Formula 1B.

In an implementation, the host may include, e.g., at least one selectedfrom a compound represented by Formula 11-HT, a compound represented byFormula 21-HT, a compound represented by Formula 31-HT, a compoundrepresented by Formula 41-HT, a compound represented by Formula 51-HT, acompound represented by Formula 61-ET, and a compound represented byFormula 71-ET:

In Formulae 11-HT, 21-HT, 31-HT, 41-HT, and 51-HT,

X₂₁ may be, e.g., O, S, N-[(L₂₄)_(a24)-R₂₄], B-[(L₂₄)_(a24)-R₂₄],P-[(L₂₄)_(a24)-R₂₄], C(R₂₄)(R₂₅), or Si(R₂₄)(R₂₅),

A₁₁, A₁₂, and A₂₁ to A₂₄ may each independently be or include, e.g., aC₅-C₃₀ carbocyclic group or a π electron-depleted nitrogen-free C₂-C₃₀heterocyclic group,

A₃₁ may be or may include, e.g., a substituted or unsubstituted C₅-C₃₀carbocyclic group in which two or more rings are condensed with eachother or a substituted or unsubstituted π electron-depletednitrogen-free C₂-C₃₀ heterocyclic group in which two or more rings arecondensed with each other, wherein A₃₁ may not be a substituted orunsubstituted spirobifluorene group and a substituted or unsubstitutedanthracene group,

L₁₁ to L₁₃, L₂₁ to L₂₅, L₃₁, L₄₁ to L₄₃, and L₅₁ to L₅₅ may eachindependently be selected from or include, e.g.,

a single bond, a C₅-C₃₀ carbocyclic group, and a π electron-depletednitrogen-free C₂-C₃₀ heterocyclic group; and

a C₅-C₃₀ carbocyclic group and a π electron-depleted nitrogen-freeC₂-C₃₀ heterocyclic group, each substituted with at least one selectedfrom hydrogen, deuterium, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a π electron-depleted nitrogen-free C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a π electron-depleted nitrogen-freeC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a π electron-depleted nitrogen-freeC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a π electron-depleted nitrogen-free monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₅₁)(Q₅₂)(Q₅₃), —N(Q₅₁)(Q₅₂), and —B(Q₅₁)(Q₅₂),

a11 to a13, a21 to a25, a31, a41 to a43, and a51 to a55 may eachindependently be, e.g., an integer from 1 to 5,

R₁₁, R₁₂, R₁₄, R₁₅, R₂₁, R₂₂, and R₂₄ to R₂₉ may each independently beselected from or include, e.g.,

hydrogen, deuterium, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a π electron-depleted nitrogen-free C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a π electron-depleted nitrogen-free C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a π electron-depleted nitrogen-free monovalent non-aromaticcondensed heteropolycyclic group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a π electron-depletednitrogen-free C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a π electron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenylgroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a π electron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, and a πelectron-depleted nitrogen-free monovalent non-aromatic condensedheteropolycyclic group, each substituted with at least one selected fromdeuterium, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a π electron-depleted nitrogen-free C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a π electron-depleted nitrogen-free monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₅₁)(Q₅₂)(Q₅₃), —N(Q₅₁)(Q₅₂), and —B(Q₅₁)(Q₅₂); and

—Si(Q₄₁)(Q₄₂)(Q₄₃), —N(Q₄₁)(Q₄₂), and —B(Q₄₁)(Q₄₂),

R₁₃, R₂₃, R₃₁, R₄₁ to R₄₃, and R₅₁ to R₅₄ may each independently beselected from or include, e.g.,

a C₃-C₁₀ cycloalkyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a πelectron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a π electron-depletednitrogen-free monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a πelectron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a π electron-depletednitrogen-free monovalent non-aromatic condensed heteropolycyclic group,each substituted with at least one selected from deuterium, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀ cycloalkyl group, a π electron-depletednitrogen-free C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a π electron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenylgroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a π electron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a πelectron-depleted nitrogen-free monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₅₁)(Q₅₂)(Q₅₃), —N(Q₅₁)(Q₅₂) and —B(Q₅₁)(Q₅₂); and

—Si(Q₄₁)(Q₄₂)(Q₄₃), —N(Q₄₁)(Q₄₂) and —B(Q₄₁)(Q₄₂).

In an implementation, R₅₁ and R₅₂ may be separate or may optionally belinked to form a saturated or unsaturated ring, and R₅₃ and R₅₄ may beseparate or may optionally be linked to form a saturated or unsaturatedring,

b31 may be, e.g., an integer from 1 to 10, and

Q₄₁ to Q₄₃ and Q₅₁ to Q₅₃ may each independently be selected from orinclude, e.g., hydrogen, deuterium, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a π electron-depleted nitrogen-free C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, a itelectron-depleted nitrogen-free monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, and a terphenyl group.

In Formulae 61-ET and 71-ET,

X₇₁ may be, e.g., O, S, N-[(L₇₄)_(a74)-R₇₄], B-[(L₇₄)_(a74)-R₇₄],P-[(L₇₄)_(a74)-R₇₄], C(R₇₄)(R₇₅), or Si(R₇₄)(R₇₅),

A₆₁, A₆₂ and A₇₁ to A₇₄ may each independently be or include, e.g., aC₅-C₃₀ carbocyclic group or a C₂-C₃₀ heterocyclic group,

L₆₁ to L₆₃ and L₇₁ to L₇₅ may each independently be selected from orinclude, e.g., a single bond, a substituted or unsubstituted C₅-C₃₀carbocyclic group, and a substituted or unsubstituted C₂-C₃₀heterocyclic group,

a61 to a63 and a71 to a75 may each independently be, e.g., an integerfrom 1 to 5, and

R₆₁ to R₆₅ and R₇₁ to R₇₉ may each independently be selected from orinclude, e.g., hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —B(Q₁)(Q₂),—C(═O)₂(Q₁), —S(═O)₂(Q₁), and —P(═O)(Q₁)(Q₂).

In an implementation, in Formula 61-ET, i) at least one selected fromA₆₁ and A₆₂ may include, e.g., a π electron-depleted nitrogen-containingC₂-C₃₀ heterocyclic group, or ii) at least one selected from R₆₁ to R₆₅may each independently be selected from or include, e.g., a substitutedor unsubstituted π electron-depleted nitrogen-containing C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted πelectron-depleted nitrogen-containing C₁-C₆₀ heteroaryl group, and asubstituted or unsubstituted π electron-depleted nitrogen-containingmonovalent non-aromatic condensed heteropolycyclic group.

In an implementation, in Formula 71-ET, i) at least one selected fromA₇₁ to A₇₄ may include, e.g., a π electron-depleted nitrogen-containingC₂-C₃₀ heterocyclic group, or ii) at least one selected from R₇₁ to R₇₃and R₇₆ to R₇₉ may each independently be selected from or include, e.g.,a substituted or unsubstituted π electron-depleted nitrogen-containingC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted πelectron-depleted nitrogen-containing C₁-C₆₀ heteroaryl group, and asubstituted or unsubstituted π electron-depleted nitrogen-containingmonovalent non-aromatic condensed heteropolycyclic group.

In an implementation, at least one substituent of the substituted C₅-C₃₀carbocyclic group, the substituted C₂-C₃₀ heterocyclic group, thesubstituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group,the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxygroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group may be selectedfrom:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)₂(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₁-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)₂(Q₂₁), —S(═O)₂(Q₂₁) and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)₂(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independentlybe selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ arylgroup substituted with a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl groupsubstituted with a C₆-C₆₀ aryl group, a terphenyl group, a C₁-C₆₀heteroaryl group, a C₁-C₆₀ heteroaryl group substituted with a C₁-C₆₀alkyl group, a C₁-C₆₀ heteroaryl group substituted with a C₆-C₆₀ arylgroup, a monovalent non-aromatic condensed polycyclic group, and amonovalent non-aromatic condensed heteropolycyclic group.

In an implementation, A₁₁, A₁₂ and A₂₁ to A₂₄ may each independently beselected from or include, e.g., a benzene group, a naphthalene group, apyrrole group, a cyclopentene group, a furan group, a thiophene group,an indole group, an indene group, a benzofuran group, a benzothiophenegroup, a carbazole group, a fluorene group, a dibenzofuran group, and adibenzothiophene group,

A₃₁ may be selected from or include, e.g., a group of Formulae A31-1 toA31-38,

A₆₁, A₆₂, and A₇₁ to A₇₄ may each independently be selected from orinclude, e.g., a benzene group, a naphthalene group, a pyrrole group, acyclopentene group, a furan group, a thiophene group, an indole group,an indene group, a benzofuran group, a benzothiophene group, a carbazolegroup, a fluorene group, a dibenzofuran group, a dibenzothiophene group,a pyridine group, a pyrimidine group, a pyrazine group, a pyridazinegroup, a triazine group, a quinoline group, an isoquinoline group, abenzoquinoline group, a benzoisoquinoline group, a quinoxaline group anda benzoquinoxaline group.

In an implementation, the host may include at least one selected from,e.g., a compound represented by Formula 11-HT, a compound represented byFormula 21-HT, a compound represented by Formula 31-HT, a compoundrepresented by Formula 41-HT, and a compound represented by Formula51-HT.

In an implementation, the host may include at least one selected from,e.g., a compound represented by Formula 61-ET and a compound representedby Formula 71-ET.

In an implementation, the compound included in the emission layer andrepresented by Formula 1A or 1B may be, e.g., an NIR-emitting compoundhaving a maximum emission wavelength of about 700 nm or more.

In an implementation, the compound included in the emission layer andrepresented by Formula 1A or 1B may be, e.g., a TADF emitter, and theemission layer may emit delayed fluorescence.

In an implementation, the first electrode of the organic light-emittingdevice may be an anode, the second electrode of the organiclight-emitting device may be a cathode, the organic layer may furtherinclude a hole transport region between the first electrode and theemission layer and an electron transport region between the emissionlayer and the second electrode, the hole transport region may include ahole injection layer, a hole transport layer, a buffer layer, anelectron blocking layer, or any combination thereof, and the electrontransport region may include a hole blocking layer, an electrontransport layer, an electron injection layer, or any combinationthereof.

In an implementation, the hole transport region may include acharge-generation material. For example, the hole transport region mayinclude a p-dopant, and the p-dopant may have a lowest unoccupiedmolecular orbital (LUMO) level of about −3.5 eV or less. For example,the p-dopant may include a cyano group-containing compound.

In an implementation, the electron transport region may include atriazole-containing compound or a benzotriazole-containing compound, andmay further include an alkali metal, an alkaline earth metal, a rareearth metal, an alkali metal compound, an alkaline earth metal compound,a rare earth metal compound, an alkali metal complex, an alkaline earthmetal complex, a rare earth metal complex, or a combination thereof.

The term “an organic layer” used herein refers to a single layer and/ora plurality of layers disposed between the first electrode and thesecond electrode of an organic light-emitting device. A materialincluded in the “organic layer” is not limited to an organic material.

[Description of FIG. 1]

FIG. 1 illustrates a schematic cross-sectional view of an organiclight-emitting device 10 according to an embodiment. The organiclight-emitting device 10 includes a first electrode 110, an organiclayer 150, and a second electrode 190.

Hereinafter, the structure of an organic light-emitting device 10according to an embodiment and a method of manufacturing an organiclight-emitting device according to an embodiment will be described inconnection with FIG. 1.

[First Electrode 110]

In an implementation, a substrate may be additionally disposed under thefirst electrode 110 or above the second electrode 190. For use as thesubstrate, the substrate may be a glass substrate or a plasticsubstrate, each having excellent mechanical strength, thermal stability,transparency, surface smoothness, ease of handling, and waterresistance.

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode 110 on the substrate. When thefirst electrode 110 is an anode, the material for forming the firstelectrode 110 may be selected from materials with a high work functionto facilitate hole injection.

The first electrode 110 may be a reflective electrode, a semi-reflectiveelectrode, or a transmissive electrode. In an implementation, when thefirst electrode 110 is a transmissive electrode, a material for forminga first electrode may be selected from indium tin oxide (ITO), indiumzinc oxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), and anycombinations thereof. In an implementation, when the first electrode 110is a semi-transmissive electrode or a reflectable electrode, a materialfor forming a first electrode may be selected from magnesium (Mg),silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca),magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), and a combinationsthereof.

In an implementation, the first electrode 110 may have a single-layeredstructure, or a multi-layered structure including two or more layers. Inan implementation, the first electrode 110 may have a three-layeredstructure of ITO/Ag/ITO.

[Organic Layer 150]

The organic layer 150 is disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport regionbetween the first electrode 110 and the emission layer and an electrontransport region between the emission layer and the second electrode190.

In an implementation, the organic layer 150 may include the heterocycliccompound according to an embodiment.

[Hole Transport Region in Organic Layer 150]

The hole transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from ahole injection layer, a first hole transport layer, a second holetransport layer, an emission auxiliary layer, and an electron blockinglayer.

In an implementation, the hole transport region may have asingle-layered structure including a single layer including a pluralityof different materials, or a multi-layered structure having a holeinjection layer/hole transport layer structure, a hole injectionlayer/hole transport layer/emission auxiliary layer structure, a holeinjection layer/emission auxiliary layer structure, a hole transportlayer/emission auxiliary layer structure, or a hole injection layer/holetransport layer/electron blocking layer structure, wherein for eachstructure, constituting layers are sequentially stacked from the firstelectrode 110 in this stated order.

In an implementation, the hole transport region may include at least oneselected from m-MTDATA, TDATA, 2-TNATA, NPB (or NPD), (3-NPB, TPD,spiro-TPD, spiro-NPB, methylated-NPB, TAPC, HMTPD,4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA),polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANI/CSA),polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound representedby Formula 201, and a compound represented by Formula 202.

In Formulae 201 and 202,

L₂₀₁ to L₂₀₄ may each independently be selected from or include, e.g., asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted orunsubstituted C₃-C₁₀ cycloalkenylene group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group,

L₂₀₅ may be selected from or include, e.g., *—O—*′, *—S—*′, *—N(Q₂₀₁)-*,a substituted or unsubstituted C₁-C₂₀ alkylene group, a substituted orunsubstituted C₂-C₂₀ alkenylene group, a substituted or unsubstitutedC₃-C₁₀ cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer from 0 to 3,

xa5 may be an integer from 1 to 10, and

R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from orinclude, e.g., a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group. a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, and asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group.

In an implementation, in Formula 202, R₂₀₁ and R₂₀₂ may optionally belinked via a single bond, a dimethyl-methylene group, or adiphenyl-methylene group, and R₂₀₃ and R₂₀₄ may optionally be linked viaa single bond, a dimethyl-methylene group, or a diphenyl-methylenegroup.

In an implementation, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from or include, e.g.,

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In an implementation, xa1 to xa4 may each independently be 0, 1, or 2.

In an implementation, xa5 may be 1, 2, 3, or 4.

In an implementation, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently beselected from or include, e.g.,

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ are respectively defined the same as described above.

In an implementation, in Formula 201, at least one selected from R₂₀₁ toR₂₀₃ may each independently be selected from or include, e.g.,

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a naphthyl group, a fluorenylgroup, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranylgroup, and a dibenzothiophenyl group.

In an implementation, in Formula 202, i) R₂₀₁ and R₂₀₂ may be linked viaa single bond, and/or ii) R₂₀₃ and R₂₀₄ may be linked via a single bond.

In an implementation, in Formula 202, at least one selected from R₂₀₁ toR₂₀₄ may be selected from or include, e.g.,

a carbazolyl group; and

a carbazolyl group substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, acarbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group.

The compound represented by Formula 201 may be represented by Formula201A:

In an implementation, the compound represented by Formula 201 may berepresented by Formula 201A(1).

In an implementation, the compound represented by Formula 201 may berepresented by Formula 201A-1.

In an implementation, the compound represented by Formula 202 may berepresented by Formula 202A.

In an implementation, the compound represented by Formula 202 may berepresented by Formula 202A-1.

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ may respectively bedefined the same as described above,

R₂₁₁ and R₂₁₂ may respectively be defined the same as described inconnection with R₂₀₃,

R₂₁3 to R₂₁₇ may each independently be selected from or include, e.g.,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group,a phenyl group substituted with a C₁-C₁₀ alkyl group, a phenyl groupsubstituted with —F, a pentalenyl group, an indenyl group, a naphthylgroup, an azulenyl group, a heptalenyl group, an indacenyl group, anacenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, an ovalenyl group, a thiophenyl group, a furanyl group, acarbazolyl group, an indolyl group, an isoindolyl group, a benzofuranylgroup, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a dibenzosilolyl group, and a pyridinyl group.

In an implementation, the hole transport region may include at least onecompound selected from Compounds HT1 to HT39.

A thickness of the hole transport region may be from about 100 Å toabout 10,000 Å, e.g., about 100 Å to about 1,000 Å. When the holetransport region includes at least one selected from a hole injectionlayer and a hole transport layer, a thickness of the hole injectionlayer may be in a range of about 100 Å to about 9,000 Å, e.g., about 100Å to about 1,000 Å, and a thickness of the hole transport layer may bein a range of about 50 Å to about 2,000 Å, e.g., about 100 Å to about1,500 Å.

In an implementation, a thickness of the first hole transport layer orthe second hole transport layer may be from about 200 Å to about 400 Å.

When the thicknesses of the hole transport region, the hole injectionlayer, and the hole transport layer are within any of these ranges,excellent hole transport characteristics may be obtained without asubstantial increase in driving voltage.

The emission auxiliary layer may help increase light emission efficiencyby compensating for an optical resonance distance according to thewavelength of light emitted by an emission layer. The electron blockinglayer may reduce or eliminate the flow of electrons from an electrontransport region. The emission auxiliary layer and the electron blockinglayer may include the aforementioned materials.

[P-Dopant]

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, for example, a p-dopant.

In an implementation, the p-dopant may have a lowest unoccupiedmolecular orbital (LUMO) level of −3.5 eV or less.

In an implementation, the p-dopant may include, e.g., at least oneselected from a quinone derivative, a metal oxide, and a cyanogroup-containing compound.

In an implementation, the p-dopant may include at least one selectedfrom, e.g.,

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221.

In Formula 221,

R₂₂₁ to R₂₂₃ may each independently be selected from or include, e.g., asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, wherein at least oneselected from R₂₂₁ to R₂₂₃ may include at least one substituent selectedfrom a cyano group, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl group substitutedwith —F, a C₁-C₂₀ alkyl group substituted with —C₁, a C₁-C₂₀ alkyl groupsubstituted with —Br, and a C₁-C₂₀ alkyl group substituted with —I.

[Emission Layer in Organic Layer 150]

When the organic light-emitting device 10 is a full color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, or a blue emission layer,according to a sub-pixel. In one or more embodiments, the emission layermay have a stacked structure, and the stacked structure may include twoor more layers selected from a red emission layer, a green emissionlayer, and a blue emission layer. The two or more layers may be indirect contact with each other. In some embodiments, the two or morelayers may be separated from each other. In one or more embodiments, theemission layer may include two or more materials. The two or morematerials may include a red light-emitting material, a greenlight-emitting material, or a blue light-emitting material. The two ormore materials may be mixed with each other in a single layer. The twoor more materials mixed with each other in the single layer may emitwhite light.

In an implementation, the emission layer may include a host and adopant. For example, the heterocyclic compound included in the emissionlayer may be a dopant, and the emission layer may further include ahost. The dopant may further include at least one selected from aphosphorescent dopant and fluorescent dopant.

In an implementation, the heterocyclic compound included in the emissionlayer may be a near infrared ray (NIR)-emitting compound having amaximum emission wavelength of 700 nm.

In an implementation, the heterocyclic compound included in the emissionlayer may be a thermally activated delayed fluorescent (TADF) emitter,and in this regard, the emission layer may emit delayed fluorescence.

In an implementation, an amount of the dopant in the emission layer maybe in a range of, e.g., about 0.01 parts by weight to about 30 parts byweight based on 100 parts by weight of the host.

In an implementation, a thickness of the emission layer may be in arange of about 100 Å to about 1,000 Å, e.g., about 200 Å to about 600 Å.When the thickness of the emission layer is within this range, excellentemission characteristics may be obtained without a substantial increasein driving voltage.

[Host in Emission Layer]

The emission layer may include a compound represented by Formula 301:

[Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21).  <Formula 301>

In an implementation, in Formula 301,

Ar₃₀₁ may be or may include, e.g., a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀ heterocyclicgroup,

xb11 may be 1, 2, or 3,

L₃₀₁ may be selected from or include, e.g., a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xb1 may be an integer from 0 to 5,

R₃₀₁ may be selected from or include, e.g., deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a substituted or unsubstitutedC₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group,a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂),—B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer from 1 to 5, and

Q₃₀₁ to Q₃₀₃ may each independently be selected from or include, e.g., aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, and a naphthyl group.

In one embodiment, in Formula 301, Ar₃₀₁ may be selected from:

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup; and

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In Formula 301, when xb11 is two or more, two or more Ar₃₀₁(s) may belinked via a single bond.

In an implementation, the compound represented by Formula 301 may berepresented by Formula 301-1 or 301-2:

In Formulae 301-1 to 301-2,

A₃₀₁ to A₃₀₄ may each independently be selected from or include, e.g., abenzene, a naphthalene, a phenanthrene, a fluoranthene, a triphenylene,a pyrene, a chrysene, a pyridine, a pyrimidine, an indene, a fluorene, aspiro-bifluorene, a benzofluorene, a dibenzofluorene, an indole, acarbazole, benzocarbazole, dibenzocarbazole, a furan, a benzofuran, adibenzofuran, a naphthofuran, a benzonaphthofuran, dinaphthofuran, athiophene, a benzothiophene, a dibenzothiophene, a naphthothiophene, abenzonaphthothiophene, and a dinaphthothiophene,

X₃₀₁ may be O, S, or N-[(L₃₀₄)_(xb4)-R₃₀₄],

R₃₁₁ to R₃₁₄ may each independently be selected from or include, e.g.,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group —Si(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and—P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ may respectively be defined the same asdescribed above,

L₃₀₂ to L₃₀₄ may each independently be defined the same as described inconnection with L₃₀₁,

xb2 to xb4 may each independently be defined the same as described inconnection with xb1, and

R₃₀₂ to R₃₀₄ may each independently be defined the same as described inconnection with R₃₀₁.

For example, in Formulae 301, 301-1, and 301-2, L₃₀₁ to L₃₀₄ may eachindependently be selected from or include, e.g.,

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may respectively be defined the same as described above.

In an implementation, in Formulae 301, 301-1, and 301-2, R₃₀₁ to R₃₀₄may each independently be selected from or include, e.g.,

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group. a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may respectively be defined the same as described above.

In an implementation, the host may include an alkaline earth metalcomplex. For example, the host may be selected from a Be complex (forexample, Compound H55), a Mg complex, and a Zn complex.

In an implementation, the host may include, e.g., at least one selectedfrom 9,10-di(2-naphthyl)anthracene (ADN),2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN),9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN),4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene(mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55and H-1a to H-15a.

[Phosphorescent Dopant Included in Emission Layer in Organic Layer 150]

The phosphorescent dopant may include an organometallic compoundrepresented by Formula 401:

In Formulae 401 and 402,

M may be selected from, e.g., iridium (Ir), platinum (Pt), palladium(Pd), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium(Eu), terbium (Tb), rhodium (Rh), and thulium (Tm),

L₄₀₁ may be selected from ligands represented by Formula 402, xc1 may be1, 2, or 3, and when xc1 is two or more, two or more L₄₀₁(s) may beidentical to or different from each other,

L₄₀₂ may be an organic ligand, xc2 may be an integer from 0 to 4, andwhen xc2 is two or more, two or more L₄₀₂(s) may be identical to ordifferent from each other,

X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon,

X₄₀₁ and X₄₀₃ may be linked via a single bond or a double bond, and X₄₀₂and X₄₀₄ may be linked via a single bond or a double bond,

A₄₀₁ and A₄₀₂ may each independently be a C₅-C₆₀ carbocyclic group or aC₁-C₆₀ heterocyclic group,

X₄₀₅ may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q₄₁₁)-*′,*—C(Q₄₁₁)(Q₄₁₂)-*, *—C(Q₄₁₁)=C(Q₄₁₂)-*, *—C(Q₄₁₁)=*′, or *═C(Q₄₁₁₎=*′,wherein Q₄₁₁ and Q₄₁₂ may each independently be hydrogen, deuterium, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, or a naphthyl group,

X₄₀₆ may be a single bond, O, or S,

R₄₀₁ and R₄₀₂ may each independently be selected from or include, e.g.,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₂₀ alkyl group, a substituted orunsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃),—N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁) (Q₄₀₂), —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and—P(═O)(Q₄₀₁)(Q₄₀₂), wherein Q₄₀₁ to Q₄₀₃ may each independently beselected from a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a C₆-C₂₀ arylgroup, and a C₁-C₂₀ heteroaryl group,

xc11 and xc12 may each independently be an integer from 0 to 10, and

* and *′ in Formula 402 each indicate a binding site to M of Formula401.

In an implementation, in Formula 402, A₄₀₁ and A₄₀₂ may eachindependently be selected from or include, e.g., a benzene group, anaphthalene group, a fluorene group, a spiro-bifluorene group, an indenegroup, a pyrrole group, a thiophene group, a furan(furan) group, animidazole group, a pyrazole group, a thiazole group, an isothiazolegroup, an oxazole group, an isoxazole group, a pyridine group, apyrazine group, a pyrimidine group, a pyridazine group, a quinolinegroup, an isoquinoline group, a benzoquinoline group, a quinoxalinegroup, a quinazoline group, a carbazole group, a benzimidazole group, abenzofuran group, a benzothiophene group, an isobenzothiophene group, abenzoxazole group, an isobenzoxazole group, a triazole group, atetrazole group, an oxadiazole group, a triazine group, a dibenzofurangroup, and a dibenzothiophene group.

In an implementation, in Formula 402, i) X₄₀₁ may be nitrogen, and X₄₀₂may be carbon, or ii) X₄₀₁ and X₄₀₂ may both be nitrogen.

In an implementation, in Formula 402, R₄₀₁ and R₄₀₂ may eachindependently be selected from or include, e.g.,

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a phenyl group, a naphthyl group, a cyclopentyl group,a cyclohexyl group, an adamantanyl group, a norbornanyl group, and anorbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

—Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁),—S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂), and

Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, and anaphthyl group.

In an implementation, in Formula 401, when xc1 is two or more, twoA₄₀₁(s) among a plurality of L₄₀₁(s) may optionally be linked via alinking group, X₄₀₇, or two A₄₀₂(s) may optionally be linked via alinking group, X₄₀₈ (see Compounds PD1 to PD4 and PD7). X₄₀₇ and X₄₀₈may each independently be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′,*—N(Q₄₁₃)-*′, *—C(Q₄₁₃)(Q₄₁₄)-*′, or *—C(Q₄₁₃)=C(Q₄₁₄)-*′ (wherein Q₄₁₃and Q₄₁₄ may each independently be hydrogen, deuterium, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, or a naphthyl group).

In an implementation, in Formula 401, L₄₀₂ may be a monovalent,divalent, or trivalent organic ligand. For example, L₄₀₂ may be selectedfrom halogen, diketone (for example, acetylacetonate), carboxylic acid(for example, picolinate), —C(═O), isonitrile, —CN, and phosphorus (forexample, phosphine and phosphite).

In an implementation, the phosphorescent dopant may be, for example,selected from Compounds PD1 to PD25.

[Fluorescent Dopant in Emission Layer]

The fluorescent dopant may include an arylamine compound or astyrylamine compound.

The fluorescent dopant may include a compound represented by Formula501:

The fluorescent dopant may include a compound represented by Formula501:

In Formula 501,

Ar₅₀₁ may be or may include, e.g., a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀ heterocyclicgroup,

L₅₀₁ to L₅₀₃ may each independently be selected from or include, e.g., asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted orunsubstituted C₃-C₁₀ cycloalkenylene group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group,

xd1 to xd3 may each independently be an integer from 0 to 3,

R₅₀₁ and R₅₀₂ may each independently be selected from or include, e.g.,a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,and

xd4 may be an integer from 1 to 6.

In an implementation, in Formula 501. Ar₅₀₁ may be selected from orinclude, e.g.,

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup; and

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In an implementation, in Formula 501, L₅₀₁ to L₅₀₃ may eachindependently be selected from or include, e.g.,

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group.

In an implementation, in Formula 501, R₅₀₁ and R₅₀₂ may eachindependently be selected from or include, e.g.,

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), and

Q₃₁ to Q₃₃ may each independently be selected from or include, e.g., aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, and a naphthyl group.

In an implementation, in Formula 501, xd4 may be 2.

In an implementation, the fluorescent dopant may be selected fromCompounds FD1 to FD22.

In an implementation, the fluorescent dopant may be selected fromcompounds below.

[Electron Transport Region in Organic Layer 150]

In an implementation, the electron transport region may have i) asingle-layered structure including a single layer including a singlematerial, ii) a single-layered structure including a single layerincluding a plurality of different materials, or iii) a multi-layeredstructure having a plurality of layers including a plurality ofdifferent materials.

In an implementation, the electron transport region may include at leastone selected from a buffer layer, a hole blocking layer, an electroncontrol layer, an electron transport layer, and an electron injectionlayer.

In an implementation, the electron transport region may have an electrontransport layer/electron injection layer structure, a hole blockinglayer/electron transport layer/electron injection layer structure, anelectron control layer/electron transport layer/electron injection layerstructure, or a buffer layer/electron transport layer/electron injectionlayer structure, wherein for each structure, constituting layers aresequentially stacked from an emission layer.

The electron transport region (e.g., a buffer layer, a hole blockinglayer, an electron control layer, or an electron transport layer in theelectron transport region) may include a metal-free compound containingat least one π electron-depleted nitrogen-containing ring.

In an implementation, the “π electron-depleted nitrogen-containing ring”indicates a C₁-C₆₀ hetercyclic group having at least one *—N=*′ moietyas a ring-forming moiety.

In an implementation, the “π electron-depleted nitrogen-containing ring”may be or may include, e.g., i) a 5-membered to 7-memberedheteromonocyclic group having at least one *—N=*′ moiety, ii) aheteropolycyclic group in which two or more 5-membered to 7-memberedheteromonocyclic groups each having at least one *—N=*′ moiety arecondensed with each other, or iii) a heteropolycyclic group in which atleast one of 5-membered to 7-membered heteromonocyclic groups, eachhaving at least one *—N=*′ moiety, is condensed with at least one C₅-C₆₀carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring may includean imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, anindazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, aphthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline,a phenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, a thiadiazol, animidazopyridine, an imidazopyrimidine, and an azacarbazole.

In an implementation, the electron transport region may include acompound represented by Formula 601:

[Ar₆₀₁]_(xe11)—[(L₆₀₁)_(xe1)-R₆₀₁]_(xe21).  <Formula 601>

In Formula 601,

Ar₆₀₁ may be or may include, e.g., a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀ heterocyclicgroup,

xe11 may be 1, 2, or 3,

L₆₀₁ may be selected from or may include, e.g., a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group;

xe1 may be an integer from 0 to 5,

R₆₀ may be selected from or may include, e.g., a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁), —S(═O)₂(Q₆₀₁), and—P(═O)(Q₆₀₁)(Q₆₀₂),

Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group, and

xe21 may be an integer from 1 to 5.

In an implementation, at least one of Ar₆₀₁(s) in the number of xe11 andR₆₀₁(s) in the number of xe21 may include the π electron-depletednitrogen-containing ring.

In an implementation, ring Ar₆₀₁ in Formula 601 may be selected from ormay include, e.g.,

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an isobenzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group; and

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an isobenzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar₆₀₁(s) may belinked via a single bond.

In an implementation, Ar₆₀₁ in Formula 601 may be an anthracene group.

In an implementation, the compound represented by Formula 601 may berepresented by Formula 601-1.

In Formula 601-1,

X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), X₆₁₆ may be N orC(R₆₁₆), and at least one selected from X₆₁₄ to X₆₁₆ may be N,

L₆₁₁ to L₆₁₃ may each independently be defined the same as described inconnection with L₆₀₁,

xe611 to xe613 may each independently be defined the same as describedin connection with xe1,

R₆₁₁ to R₆₁₃ may each independently be defined the same as described inconnection with R₆₀₁, and

R₆₁₄ to R₆₁₆ may each independently be selected from or include, e.g.,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, and a naphthyl group.

In an implementation, the L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and601-1 may each independently be selected from or include, e.g.,

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group.

In an implementation, xe1 and xe611 to xe613 in Formulae 601 and 601-1may each independently be 0, 1, or 2.

In an implementation, in Formulae 601 and 601-1, R₆₀₁ and R₆₁₁ to R₆₁₃may each independently be selected from or include, e.g.,

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group. anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

—S(═O)₂(Q₆₀₁) and —P(═O)(Q₆₀₁)(Q₆₀₂), and

Q₆₀₁ and Q₆₀₂ may respectively be defined the same as described above.

In an implementation, the electron transport region may include at leastone compound selected from Compounds ET1 to ET36.

In an implementation, the electron transport region may include at leastone compound selected from 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline(BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq3, BAlq,3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ), and NTAZ:

Thicknesses of the buffer layer, the hole blocking layer, and theelectron control layer may each be in a range of about 20 Å to about1,000 Å, e.g., about 30 Å to about 300 Å. When the thicknesses of thebuffer layer, the hole blocking layer, and the electron control layerare within these ranges, the electron blocking layer may have excellentelectron blocking characteristics or electron control characteristicswithout a substantial increase in driving voltage.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, e.g., about 150 Å to about 500 Å. When thethickness of the electron transport layer is within the range describedabove, the electron transport layer may have satisfactory electrontransport characteristics without a substantial increase in drivingvoltage.

The electron transport region (e.g., the electron transport layer in theelectron transport region) may further include, in addition to thematerials described above, a metal-containing material.

In an implementation, the metal-containing material may include at leastone selected from an alkali metal complex and an alkaline earth metalcomplex. The alkali metal complex may include a metal ion selected froma Li ion, a Na ion, a K ion, a Rb ion, and a Cs ion, and the alkalineearth-metal complex may include a metal ion selected from a Be ion, a Mgion, a Ca ion, a Sr ion, and a Ba ion. In an implementation, a ligandcoordinated with the metal ion of the alkali metal complex or thealkaline earth-metal complex may be selected from a hydroxy quinoline, ahydroxy isoquinoline, a hydroxy benzoquinoline, a hydroxy acridine, ahydroxy phenanthridine, a hydroxy phenyloxazole, a hydroxyphenylthiazole, a hydroxy diphenyloxadiazole, a hydroxydiphenylthiadiazol, a hydroxy phenylpyridine, a hydroxyphenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, aphenanthroline, and a cyclopentadiene.

In an implementation, the metal-containing material may include a Licomplex. In an implementation, the Li complex may include, e.g.,Compound ET-D1 (lithium quinolate, LiQ) or ET-D2.

The electron transport region may include an electron injection layerthat facilitates injection of electrons from the second electrode 190.The electron injection layer may directly contact the second electrode190.

In an implementation, the electron injection layer may have i) asingle-layered structure including a single layer including a singlematerial, ii) a single-layered structure including a single layerincluding a plurality of different materials, or iii) a multi-layeredstructure having a plurality of layers including a plurality ofdifferent materials.

In an implementation, the electron injection layer may include an alkalimetal, an alkaline earth metal, a rare earth metal, an alkali metalcompound, an alkaline earth-metal compound, a rare earth metal compound,an alkali metal complex, an alkaline earth-metal complex, a rare earthmetal complex, or a combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In oneembodiment, the alkali metal may be Li, Na, or Cs. In an implementation,the alkali metal may be Li or Cs.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and therare earth metal compound may be selected from oxides and halides (forexample, fluorides, chlorides, bromides, or iodides) of the alkalimetal, the alkaline earth-metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides, suchas Li₂O, Cs₂O, or K₂O, and alkali metal halides, such as LiF, NaF, CsF,KF, LiI, NaI, CsI, or KI. In an implementation, the alkali metalcompound may be selected from LiF, Li₂O, NaF, LiI, NaI, CsI, and KI.

The alkaline earth-metal compound may be selected from alkalineearth-metal compounds, such as BaO, SrO, CaO, BaxSr_(1-x)O (0<x<1), orBa_(x)Ca_(1-x)O (0<x<1). In an implementation, the alkaline earth-metalcompound may be selected from BaO, SrO, and CaO.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃,Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In an implementation, the rare earth metalcompound may be selected from YbF₃, ScF₃, TbF₃, YbI₃, ScI₃, and Tb₃.

In an implementation, the alkali metal complex, the alkaline earth-metalcomplex, and the rare earth metal complex may include an ion of alkalimetal, alkaline earth-metal, and rare earth metal as described above,and a ligand coordinated with a metal ion of the alkali metal complex,the alkaline earth-metal complex, or the rare earth metal complex may beselected from hydroxy quinoline, hydroxy isoquinoline, hydroxybenzoquinoline, hydroxy acridine, hydroxy phenanthridine, hydroxyphenyloxazole, hydroxy phenylthiazole, hydroxy diphenyloxadiazole,hydroxy diphenylthiadiazol, hydroxy phenylpyridine, hydroxyphenylbenzimidazole, hydroxy phenylbenzothiazole, bipyridine,phenanthroline, and cyclopentadiene.

The electron injection layer may consist of or include an alkali metal,an alkaline earth metal, a rare earth metal, an alkali metal compound,an alkaline earth-metal compound, a rare earth metal compound, an alkalimetal complex, an alkaline earth-metal complex, a rare earth metalcomplex, or any combinations thereof, as described above. In animplementation, the electron injection layer may further include anorganic material. When the electron injection layer further includes anorganic material, an alkali metal, an alkaline earth metal, a rare earthmetal, an alkali metal compound, an alkaline earth-metal compound, arare earth metal compound, an alkali metal complex, an alkalineearth-metal complex, a rare earth metal complex, or any combinationsthereof may be homogeneously or non-homogeneously dispersed in a matrixincluding the organic material.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, e.g., about 3 Å to about 90 Å. When the thickness ofthe electron injection layer is within the range described above, theelectron injection layer may have satisfactory electron injectioncharacteristics without a substantial increase in driving voltage.

[Second Electrode 190]

The second electrode 190 may be disposed on the organic layer 150 havingsuch a structure. The second electrode 190 may be a cathode which is anelectron injection electrode, and in this regard, a material for formingthe second electrode 190 may be selected from metal, an alloy, anelectrically conductive compound, and a combination thereof, which havea relatively low work function.

In an implementation, the second electrode 190 may include, e.g., atleast one selected from lithium (L₁), silver (Ag), magnesium (Mg),aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium(Mg—In), magnesium-silver (Mg—Ag), ITO, and IZO. The second electrode190 may be a transmissive electrode, a semi-transmissive electrode, or areflective electrode.

The second electrode 190 may have a single-layered structure, or amulti-layered structure including two or more layers.

[Description of FIGS. 2 to 4]

An organic light-emitting device 20 of FIG. 2 may include a firstcapping layer 210, a first electrode 110, an organic layer 150, and asecond electrode 190 which are sequentially stacked in this statedorder, an organic light-emitting device 30 of FIG. 3 may include a firstelectrode 110, an organic layer 150, a second electrode 190, and asecond capping layer 220 which are sequentially stacked in this statedorder, and an organic light-emitting device 40 of FIG. 4 may include afirst capping layer 210, a first electrode 110, an organic layer 150, asecond electrode 190, and a second capping layer 220.

Regarding FIGS. 2 to 4, the first electrode 110, the organic layer 150,and the second electrode 190 may be understood by referring to thedescription presented in connection with FIG. 1.

In the organic layer 150 of each of the organic light-emitting devices20 and 40, light generated in an emission layer may pass through thefirst electrode 110, which is a semi-transmissive electrode or atransmissive electrode, and the first capping layer 210 toward theoutside, and in the organic layer 150 of each of the organiclight-emitting devices 30 and 40, light generated in an emission layermay pass through the second electrode 190, which is a semi-transmissiveelectrode or a transmissive electrode, and the second capping layer 220toward the outside.

The first capping layer 210 and the second capping layer 220 may helpincrease external luminescent efficiency according to the principle ofconstructive interference.

In an implementation, the first capping layer 210 and the second cappinglayer 220 may each independently be an organic capping layer includingan organic material, an inorganic capping layer including an inorganicmaterial, or a composite capping layer including an organic material andan inorganic material.

At least one selected from the first capping layer 210 and the secondcapping layer 220 may include at least one material selected from, e.g.,carbocyclic compounds, heterocyclic compounds, amine-based compounds,porphyrine derivatives, phthalocyanine derivatives, a naphthalocyaninederivatives, alkali metal complexes, and alkaline earth-based complexes.The carbocyclic compound, the heterocyclic compound, and the amine-basedcompound may be optionally substituted with a substituent containing atleast one element selected from O, N, S, Se, Si, F, Cl, Br, and I. Inone embodiment, at least one selected from the first capping layer 210and the second capping layer 220 may each independently include anamine-based compound.

In an implementation, at least one selected from the first capping layer210 and the second capping layer 220 may include the compoundrepresented by Formula 201 or the compound represented by Formula 202.

In an implementation, the at least one selected from the first cappinglayer 210 and the second capping layer 220 may include a compoundselected from Compounds HT28 to HT33 and Compounds CP1 to CP5

Hereinbefore, the organic light-emitting device according to anembodiment has been described in connection with FIGS. 1 to 4.

Layers constituting the hole transport region, an emission layer, andlayers constituting the electron transport region may be formed in acertain region by using one or more suitable methods selected fromvacuum deposition, spin coating, casting, Langmuir-Blodgett (LB)deposition, ink-jet printing, laser-printing, and laser-induced thermalimaging.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed byvacuum deposition, the deposition may be performed at, e.g., adeposition temperature of about 100° C. to about 500° C., a vacuumdegree of about 10⁻⁸ torr to about 10⁻³ torr, and/or a deposition speedof about 0.01 Å/sec to about 100 Å/sec by taking into account a materialto be included in a layer to be formed, and the structure of a layer tobe formed.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed by spincoating, the spin coating may be performed at, e.g., a coating speed ofabout 2,000 rpm to about 5,000 rpm and/or at a heat treatmenttemperature of about 80° C. to about 200° C. by taking into account amaterial to be included in a layer to be formed, and the structure of alayer to be formed.

[General Definition of Substituents]

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear orbranched aliphatic saturated hydrocarbon monovalent group having 1 to 60carbon atoms, and examples thereof include a methyl group, an ethylgroup, a propyl group, an isobutyl group, a sec-butyl group, atert-butyl group, a pentyl group, an isoamyl group, and a hexyl group.The term “C₁-C₆₀ alkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbongroup having at least one carbon-carbon double bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group, and examples thereof include anethenyl group, a propenyl group, and a butenyl group. The term “C₂-C₆₀alkenylene group” as used herein refers to a divalent group having thesame structure as the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a hydrocarbongroup having at least one carbon-carbon triple bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group, and examples thereof include anethynyl group, and a propynyl group. The term “C₂-C₆₀ alkynylene group”as used herein refers to a divalent group having the same structure asthe C₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group),and examples thereof include a methoxy group, an ethoxy group, and anisopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalentsaturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, andexamples thereof include a cyclopropyl group, a cyclobutyl group, acyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term“C₃-C₁₀ cycloalkylene group” as used herein refers to a divalent grouphaving the same structure as the C₃-C₁₀ cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to amonovalent monocyclic group having at least one heteroatom selected fromN, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms, andexamples thereof include a 1,2,3,4-oxatriazolidinyl group, atetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₁₀ heterocycloalkyl group.

The term C₃-C₁₀ cycloalkenyl group used herein refers to a monovalentmonocyclic group that has 3 to 10 carbon atoms and at least onecarbon-carbon double bond in the ring thereof and no aromaticity, andexamples thereof include a cyclopentenyl group, a cyclohexenyl group,and a cycloheptenyl group. The term “C₃-C₁₀ cycloalkenylene group” asused herein refers to a divalent group having the same structure as theC₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to amonovalent monocyclic group that has at least one heteroatom selectedfrom N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms,and at least one double bond in its ring. Non-limiting examples of theC₁-C₁₀ heterocycloalkenyl group include a4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, anda 2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkenylenegroup” as used herein refers to a divalent group having the samestructure as the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms, and aC₆-C₆₀ arylene group used herein refers to a divalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms. Non-limitingexamples of the C₆-C₆₀ aryl group include a phenyl group, a naphthylgroup, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, anda chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylenegroup each include two or more rings, the rings may be fused to eachother.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalentgroup having a heterocyclic aromatic system that has at least oneheteroatom selected from N, O, Si, P, and S as a ring-forming atom, inaddition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylene group”as used herein refers to a divalent group having a heterocyclic aromaticsystem that has at least one heteroatom selected from N, O, Si, P, and Sas a ring-forming atom, in addition to 1 to 60 carbon atoms.Non-limiting examples of the C₁-C₆₀ heteroaryl group include a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachinclude two or more rings, the rings may be condensed with each other.

The term “C₆-C₆₀ aryloxy group” as used herein refers to —OA₁₀₂ (whereinA₁₀₂ is the C₆-C₆₀ aryl group), and a C₆-C₆₀ arylthio group used hereinindicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein refers to a monovalent group having two or more rings condensedwith each other, only carbon atoms as ring-forming atoms (for example,having 8 to 60 carbon atoms), and no aromaticity in its entire molecularstructure. An example of the monovalent non-aromatic condensedpolycyclic group is a fluorenyl group. The term “divalent non-aromaticcondensed polycyclic group” as used herein refers to a divalent grouphaving the same structure as the monovalent non-aromatic condensedpolycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein refers to a monovalent group having two or more ringscondensed to each other, at least one heteroatom selected from N, O, Si,P, and S, other than carbon atoms (for example, having 1 to 60 carbonatoms), as a ring-forming atom, and no aromaticity in its entiremolecular structure. An example of the monovalent non-aromatic condensedheteropolycyclic group is a carbazolyl group. The term “divalentnon-aromatic condensed heteropolycyclic group” as used herein refers toa divalent group having the same structure as the monovalentnon-aromatic condensed heteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein refers to amonocyclic or polycyclic group having 5 to 60 carbon atoms in which aring-forming atom is a carbon atom only. The C₅-C₆₀ carbocyclic groupmay be an aromatic carbocyclic group or a non-aromatic carbocyclicgroup. The C₅-C₆₀ carbocyclic group may be a ring, such as benzene, amonovalent group, such as a phenyl group, or a divalent group, such as aphenylene group. In one or more embodiments, depending on the number ofsubstituents connected to the C₅-C₆₀ carbocyclic group, the C₅-C₆₀carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C₁-C₆₀ heterocyclic group” as used herein refers to a grouphaving the same structure as the C₁-C₆₀ carbocyclic group, except thatas a ring-forming atom, at least one heteroatom selected from N, O, Si,P, and S is used in addition to carbon (the number of carbon atoms maybe in a range of 1 to 60).

At least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the substituted divalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀ alkenyl group, the substitutedC₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, thesubstituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group may be selectedfrom:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-Cooheteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

The term “Ph” or “ph” used herein refers to a phenyl group, the term“Me” used herein refers to a methyl group, the term “Et” used hereinrefers to an ethyl group, the term “ter-Bu” or “Bu′” used herein refersto a tert-butyl group, and the term “OMe” used herein refers to amethoxy group.

The term “biphenyl group” as used herein refers to “a phenyl groupsubstituted with a phenyl group.” In other words, the “biphenyl group”is a substituted phenyl group having a C₆-C₆₀ aryl group as asubstituent.

The term “terphenyl group” as used herein refers to “a phenyl groupsubstituted with a biphenyl group.” In other words, the “terphenylgroup” is a phenyl group having, as a substituent, a C₆-C₆₀ aryl groupsubstituted with a C₆-C₆₀ aryl group.

* and *′ used herein, unless defined otherwise, each refer to a bindingsite to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to embodiments and an organiclight-emitting device according to embodiments will be described indetail with reference to Synthesis Examples and Examples. The wording “Bwas used instead of A” used in describing Synthesis Examples refers tothat an identical molar equivalent of B was used in place of A.

The following Examples and Comparative Examples are provided in order tohighlight characteristics of one or more embodiments, but it will beunderstood that the Examples and Comparative Examples are not to beconstrued as limiting the scope of the embodiments, nor are theComparative Examples to be construed as being outside the scope of theembodiments. Further, it will be understood that the embodiments are notlimited to the particular details described in the Examples andComparative Examples.

SYNTHESIS EXAMPLES Synthesis Example 1: Synthesis of Compound 1

1) Synthesis of Compound 1-1

4-bromobenzaldehyde (1 eq.), Pd(OAc)₂ (0.05 eq.), P(t-Bu)₃ (0.5 eq.),and NaOt-Bu (1 eq.) were dissolved in a toluene solvent in a nitrogenatmosphere, and 9,9-dimethyl-9,10-dihydroacridine (1 eq.) was addedthereto. Then, the reaction mixture was stirred under reflux for 12hours. After the reaction mixture was cooled to ambient temperature,distilled water was slowly added thereto, and an organic layer wasextracted therefrom by using dichloromethane. The extracted organiclayer was dried by using MgSO₄ and concentrated under vacuum. Then, theresult obtained therefrom was purified by column chromatography toobtain Compound 1-1 (yield: 87%).

2) Synthesis of Compound 1-2

Cp₂TiCl₂ (1.2 eq.) was dissolved in a tetrahydrofuran (THF) solventunder a nitrogen atmosphere at a temperature of −78° C. and sec-BuMgCl(1.2 eq.) was added to the mixture. The mixture was stirred at atemperature of −78° C. for 2 hours, slowly heated to ambienttemperature, and stirred for 30 minutes. The mixture was cooled to atemperature of −78° C. and Compound 1-1 (1 eq.) was added thereto andstirred for 3 hours. After the reaction was completed, distilled waterwas slowly added to the mixture, and a solid obtained therefrom wasfiltered and washed using an ethyl ether solvent. Then, an organic layerwas extracted therefrom by using dichloromethane. The extracted organiclayer was dried by using MgSO₄ and concentrated under vacuum. Then, theresult obtained therefrom was purified by column chromatography usingethyl acetate/hexane to obtain Compound 1-2 (yield: 66%).

3) Synthesis of Compound 1-3

Compound 1-2 (1 eq.) and N-bromosuccinimide (2.2 eq.) were dissolved ina CCl₄ solvent and the mixture was stirred under reflux for 5 hours. Asolid obtained therefrom was filtered and washed by using an ethyl ethersolvent. Then, an organic layer was extracted therefrom by usingdichloromethane. The extracted organic layer was dried by using MgSO₄and concentrated under vacuum. Then, the result obtained therefrom waspurified by column chromatography using ethyl acetate/hexane to obtainCompound 1-3 (yield: 42%).

4) Synthesis of Compound 1

Compound 1-3 (1 eq.) and sulfamide (5 eq.) were dissolved in anhydrousethanol, and HCl gas was added thereto while stirring the mixture underreflux for 8 hours. After the reaction was completed, distilled waterwas slowly added to the mixture, and an organic layer was extractedtherefrom by using dichloromethane. The extracted organic layer wasdried by using MgSO₄ and concentrated under vacuum. Then, the resultobtained therefrom was purified by column chromatography using ethylacetate/hexane to obtain Compound 1 (yield: 31%).

Synthesis Example 2: Synthesis of Compound 5

1) Synthesis of Compound 5-1

5-bromothiophene-2-carbaldehyde (1 eq.) and Pd(OAc)₂ (0.05 eq.),P(t-Bu)₃ (0.5 eq.), and NaOt-Bu (1 eq.) were dissolved in a toluenesolvent under a nitrogen atmosphere, and9,9-dimethyl-9,10-dihydroacridine (1 eq.) was added thereto. Then, thereaction mixture was stirred under reflux for 12 hours. The reactionmixture was cooled to ambient temperature, and distilled water was addedthereto. Then, an organic layer was extracted therefrom by usingdichloromethane. The extracted organic layer was dried by using MgSO₄and concentrated under vacuum. Then, the result obtained therefrom waspurified by column chromatography to obtain Compound 5-1 (yield: 72%).

2) Synthesis of Compound 5-2

Cp₂TiCl₂ (1.2 eq.) was dissolved in a THF solvent at a temperature of−78° C. under a nitrogen atmosphere, and sec-BuMgCl (1.2 eq.) was addedto the mixture. The mixture was stirred at a temperature of −78° C. for2 hours, slowly heated to ambient temperature, and stirred for 30minutes. The mixture was cooled to a temperature of −78° C. and Compound5-1 (1 eq.) was added thereto and stirred for 3 hours. After thereaction was completed, distilled water was slowly added to the mixture,and a solid obtained therefrom was filtered and washed by using an ethylether solvent. Then, an organic layer was extracted therefrom by usingdichloromethane. The extracted organic layer was dried by using MgSO₄and concentrated under vacuum. The result obtained therefrom waspurified by column chromatography using ethyl acetate/hexane to obtainCompound 5-2 (yield: 53%).

3) Synthesis of Compound 5-3

Compound 5-2 (1 eq.) and N-bromosuccinimide (2.2 eq.) were dissolved ina CCl₄ solvent, and the mixture was stirred under reflux for 5 hours. Asolid obtained therefrom was filtered and washed by using an ethyl ethersolvent. Then, an organic layer was extracted therefrom by usingdichloromethane. The extracted organic layer was dried by using MgSO₄and concentrated under vacuum. Then, the result obtained therefrom waspurified by column chromatography using ethyl acetate/hexane to obtainCompound 5-3 (yield: 40%).

4) Synthesis of Compound 5

Compound 5-3 (1 eq.) and sulfamide (5 eq.) were dissolved in anhydrousethanol, and HCl gas was added thereto while stirring the mixture underreflux for 8 hours. After the reaction was completed, distilled waterwas slowly added to the mixture, and an organic layer was extractedtherefrom by using dichloromethane. The extracted organic layer wasdried by using MgSO₄ and concentrated under vacuum. Then, the resultobtained therefrom was purified by column chromatography using ethylacetate/hexane to obtain Compound 5 (yield: 33%).

Synthesis Example 3: Synthesis of Compound 16

1) Synthesis of Compound 16-1

Cp₂TiCl₂ (1.2 eq.) was dissolved in a THF solvent under a nitrogenatmosphere at a temperature of −78° C. and sec-BuMgCl (1.2 eq.) wasadded to the mixture. The mixture was stirred at a temperature of −78°C. for 2 hours, slowly heated to ambient temperature, and stirred for 30minutes. The mixture was cooled to a temperature of −78° C. andbenzaldehyde (1 eq.) was added thereto and stirred for 3 hours. Afterthe reaction was completed, distilled water was slowly added to themixture, and a solid obtained therefrom was filtered and washed by usingan ethyl ether solvent. Then, an organic layer was extracted therefromby using dichloromethane. The extracted organic layer was dried by usingMgSO₄ and concentrated under vacuum. Then, the result obtained therefromwas purified by column chromatography using ethyl acetate/hexane toobtain Compound 16-1 (yield: 80%).

2) Synthesis of Compound 16-2

Compound 16-1 (1 eq.) and N-bromosuccinimide (2.2 eq.) were dissolved ina CCl₄ solvent and the mixture was stirred under reflux for 5 hours. Asolid obtained therefrom was filtered and washed by using an ethyl ethersolvent. Then, an organic layer was extracted therefrom by usingdichloromethane. The extracted organic layer was dried by using MgSO₄and concentrated under vacuum. Then, the result obtained therefrom waspurified by column chromatography using ethyl acetate/hexane to obtainCompound 16-2 (yield: 49%).

3) Synthesis of Compound 16-3

Compound 16-2 (1 eq.) and sulfamide (5 eq.) were dissolved in anhydrousethanol, and HCl gas was added thereto while stirring the mixture underreflux for 8 hours. After the reaction was completed, distilled waterwas slowly added to the mixture, and an organic layer was extractedtherefrom by using dichloromethane. The extracted organic layer wasdried by using MgSO₄ and concentrated under vacuum. Then, the resultobtained therefrom was purified by column chromatography using ethylacetate/hexane to obtain Compound 16-3 (yield: 49%).

4) Synthesis of Compound 16-4

Compound 16-3 was dissolved in anhydrous dichloromethane at atemperature of 0° C. under a nitrogen atmosphere, and anhydrousaluminium chloride (4 eq.) was added thereto and stirred for 3 hours atambient temperature. Ice water was added to the mixture, and washing wasperformed thereon by using dichloromethane. Then, a solid obtainedtherefrom was filtered and dried (yield: 47%).

5) Synthesis of Compound 16-5

Compound 16-4 (1 eq.) was dissolved in a THF solvent under a nitrogenatmosphere. N-bromosuccinimide (2.2 eq.) dissolved in a small amount ofTHF was slowly added to the reaction mixture at a temperature of 0° C.without light and stirred at ambient temperature for 8 hours. After thereaction was completed, distilled water was slowly added thereto, and anorganic layer was extracted therefrom by using dichloromethane. Theextracted organic layer was dried by using MgSO₄ and concentrated undervacuum. Then, the result obtained therefrom was purified by columnchromatography using ethyl acetate/hexane to obtain Compound 16-5(yield: 72%).

6) Synthesis of Compound 16-6

Compound 16-5 (1 eq.), Pd(Ph₃)₄ (0.05 eq.), and K₂CO₃ (1.2 eq.) weredissolved in toluene under a nitrogen atmosphere, and(4-bromophenyl)boronic acid (2.3 eq.) dissolved in a small amount oftoluene was added thereto. The reaction mixture was stirred under refluxfor 15 hours. After the reaction was completed, the reaction mixture wascooled to ambient temperature, and distilled water was slowly addedthereto. Then, an organic layer was extracted therefrom by usingdichloromethane. The extracted organic layer was dried by using MgSO₄and concentrated under vacuum. Then, the result obtained therefrom waspurified by column chromatography using ethyl acetate/hexane to obtainCompound 16-6 (yield: 46%).

7) Synthesis of Compound 16

Compound 16-6 (1 eq.), 9,9-dimethyl-9,10-dihydroacridine (2 eq.),Pd(OAc)₂ (0.05 eq.), P(t-Bu)₃ (50 wt %, 0.05 eq.), and NaOt-Bu (sodiumtert-butoxide, 2 eq.) were stirred with a toluene solvent under anitrogen atmosphere. Then, the mixture was stirred under reflux for 12hours at a temperature of 120° C. After the reaction was completed, themixture was cooled to ambient temperature, and an organic layer wasextracted therefrom by using water and dichloromethane. The extractedorganic layer was dried by using MgSO₄ and concentrated under vacuum.Then, the result obtained therefrom was purified by columnchromatography using ethyl acetate/hexane to obtain Compound 16 (yield:59%).

Synthesis Example 4: Synthesis of Compound 17

1) Synthesis of Compound 17-1

Compound 17-1 (yield: 52%) was synthesized in the same manner as inSynthesis of Compound 16-6, except that (5-bromothiophen-2-yl)boronicacid was used instead of (4-bromophenyl)boronic acid.

2) Synthesis of Compound 17

Compound 17 (yield: 50%) was synthesized in the same manner as inSynthesis of Compound 16, except that Compound 17-1 was used instead ofCompound 16-6.

¹H NMR and MS/FAB of Compounds synthesized in Synthesis Examples 1 to 4are shown in Table 1.

Synthesis methods of compounds other than Compounds shown in Table 1 mayalso be recognized by those of ordinary skill in the art by referring tothe synthesis mechanisms and source materials described above.

TABLE 1 MS/FAB Compound ¹H NMR (CDCl₃, 400 MHz) found calc. 1 δ =7.44(d, 4H), 7.26(d, 4H), 7.07(d, 4H), 684.26 684.86 7.14(t, 4H),7.11(d, 4H) 6.89(t, 4H), 1.69(s, 12H) 5 δ = 7.14(t, 4H), 7.11(d, 4H),7.07(d, 4H), 696.17 696.90 6.89(t, 4H), 6.70(d, 2H) 5.98(d, 2H), 1.69(s,12H) 16 δ = 8.17(s, 2H), 8.04(d, 4H), 7.14(t, 4H), 834.30 835.04 7.11(d,4H), 7.07(d, 4H), 6.85(d, 2H) 5.98(d, 2H), 1.69(s, 12H) 17 δ = 8.20(s,2H), 8.14(m, 4H), 7.55(d, 4H), 846.22 847.08 7.27(d, 4H), 7.14(t, 4H),7.11(d, 4H), 6.89(t, 4H), 1.69(s, 12H)

EXAMPLES Example 1

An ITO film (anode) having a thickness of 120 nm was formed on a glasssubstrate, and ultrasonic cleaning and pre-treatment (UV—O₃ treatment,thermal treatment) were performed thereon.

Compound HT3 and HAT-CN were co-deposited on the anode at a weight ratioof 99:1 to form a hole transport layer having a thickness of 120 nm.

Then, a host (Compound H-1a) and a dopant (Compound 1, 1 wt %) wereco-deposited on the hole transport layer to form an emission layerhaving a thickness of 30 nm.

Then, ET1 was deposited on the emission layer to form a buffer layerhaving a thickness of 5 nm, ET2 was deposited on the buffer layer toform an electron transport layer having a thickness of 25 nm, LiF wasdeposited on the electron transport layer to form an electron injectionlayer having a thickness of 0.5 nm, and A1 was vacuum-deposited on theelectron injection layer to form a cathode having a thickness of 150 nm,thereby completing the manufacture of an organic light-emitting device.

Examples 2 to 4 and Comparative Example 1

Organic light-emitting devices were manufactured in the same manner asin Example 1, except that Compounds shown in Table 2 were each usedinstead of Compound 1 as a dopant in forming the emission layer.

Evaluation Example 1

The driving voltage, current density, luminance, external quantumefficiency (EQE), and maximum emission wavelength of the organiclight-emitting devices manufactured according to Examples 1 to 4 andComparative Example 1 were measured by using Keithley SMU 236 and aluminance meter PR745, and results thereof are shown in Table 2.

TABLE 2 Maximum Driving emission Dopant HOMO LUMO S₁ ΔE_(ST) voltage EQEwavelength compound (eV) (eV) (eV) (eV) (V) (%) (nm) Example 1 Compound1−5.46 −3.54 1.51 0.01 6.7 2.3 819 Example 2 Compound 5 −5.66 −3.51 1.700.01 6.5 2.7 730 Example 3 Compound 16 −5.40 −3.79 1.35 0.00 7.1 0.9 917Example 4 Compound 17 −5.57 −3.75 1.55 0.01 7.1 1.2 801 Comparative PtPc−5.08 −2.74 1.32 (T₁) 0.86 7.9 0.5 968 Example 1

Referring to Table 2, it may be seen that the organic light-emittingdevices of Examples 1 to 4 had high external quantum efficiency, ascompared with the organic light-emitting device of Comparative Example 1(that employed Pt phthalocyanine (PtPc) as a dopant compound), and mayenable a long wavelength shift of a maximum emission wavelength, andthus may be suitable for NIR emission.

Organic light-emitting devices including the heterocyclic compoundaccording to an embodiment may have a low driving voltage, highefficiency, high luminance, and a long lifespan, and high-qualityorganic light-emitting devices and organic light-emitting apparatusesmay be implemented.

The embodiments may provide a heterocyclic compound and an organiclight-emitting device including the same.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. An organic light-emitting device, comprising: afirst electrode; a second electrode facing the first electrode; and anorganic layer between the first electrode and the second electrode andincluding an emission layer, wherein the emission layer includes acompound represented by Formula 1A or a compound represented by Formula1B:

wherein, in Formulae 1A and 1B, ring A₁ is selected from a C₅-C₆₀carbocyclic group and a C₂-C₆₀ heterocyclic group, X₁ is S or Se, L₁ andL₂ are each independently selected from a substituted or unsubstitutedC₅-C₆₀ carbocyclic group and a substituted or unsubstituted C₂-C₆₀heterocyclic group, a1 and a2 are each independently an integer from 0to 5, when a1 is 2, 3, 4, or 5, the 2, 3, 4, or 5 L₁(s) are identical toor different from each other, and when a2 is 2, 3, 4, or 5, the 2, 3, 4,or 5 L₂(s) are identical to or different from each other, when a1 is 0,*-(L₁)_(a1)-*′ is a single bond, and when a2 is 0, *-(L₂)_(a2)-*′ is asingle bond, R₁ and R₂ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazino group, a hydrazonogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₂-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₆₀ cycloalkenyl group, a substituted orunsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂),—P(═S)(Q₁)(Q₂), —S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂), at least one of R₁and R₂ is an electron donating group, b1 and b2 are each independentlyan integer from 1 to 10, when b1 is 2, 3, 4, 5, 6, 7, 8, 9, or 10, the2, 3, 4, 5, 6, 7, 8, 9, or 10 R₁(s) are identical to or different fromeach other, and when b2 is 2, 3, 4, 5, 6, 7, 8, 9, or 10, the 2, 3, 4,5, 6, 7, 8, 9, or 10 R₂(s) are identical to or different from eachother, c1 and c2 are each independently an integer from 1 to 10, atleast one substituent of the substituted C₅-C₆₀ carbocyclic group, thesubstituted C₂-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group,the substituted C₁-C₆₀ heteroaryl group, the substituted C₁-C₆₀heteroaryloxy group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group is selected from: deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazino group, ahydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),—S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and —Si(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and—P(═O)(Q₃₁)(Q₃₂), Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group, and and *′ each indicate abinding site to a neighboring atom.
 2. The organic light-emitting deviceas claimed in claim 1, wherein: the emission layer includes a host and adopant, the dopant includes the compound represented by Formula 1A orFormula 1B, and the host includes at least one selected from a compoundrepresented by Formula 11-HT, a compound represented by Formula 21-HT, acompound represented by Formula 31-HT, a compound represented by Formula41-HT, a compound represented by Formula 51-HT, a compound representedby Formula 61-ET, and a compound represented by Formula 71-ET:

wherein, in Formulae 11-HT, 21-HT, 31-HT, 41-HT, and 51-HT, X₂₁ is O, S,N-[(L₂₄)_(a24)-R₂₄], B-[(L₂₄)_(a24)-R₂₄], P-[(L₂₄)_(a24)-R₂₄],C(R₂₄)(R₂₅), or Si(R₂₄)(R₂₅), A₁₁, A₁₂, and A₂₁ to A₂₄ are eachindependently a C₅-C₃₀ carbocyclic group or a π electron-depletednitrogen-free C₂-C₃₀ heterocyclic group, A₃₁ is a substituted orunsubstituted C₅-C₃₀ carbocyclic group in which two or more rings arecondensed with each other or a substituted or unsubstituted πelectron-depleted nitrogen-free C₂-C₃₀ heterocyclic group in which twoor more rings are condensed with each other, wherein A₃₁ is not asubstituted or unsubstituted spirobifluorene group and a substituted orunsubstituted anthracene group, L₁₁ to L₁₃, L₂₁ to L₂₅, L₃₁, L₄₁ to L₄₃,and L₅₁ to L₅₅ are each independently selected from: a single bond, aC₅-C₃₀ carbocyclic group, and a π electron-depleted nitrogen-free C₂-C₃₀heterocyclic group; and a C₅-C₃₀ carbocyclic group and a πelectron-depleted nitrogen-free C₂-C₃₀ heterocyclic group, eachsubstituted with at least one selected from hydrogen, deuterium, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a π electron-depletednitrogen-free C₁-C₁₀ heterocycloalkyl group, a C₃-C₀ cycloalkenyl group,a π electron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a πelectron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a π electron-depletednitrogen-free monovalent non-aromatic condensed heteropolycyclic group,a biphenyl group, a terphenyl group, —Si(Q₅)(Q₅₂)(Q₅₃), —N(Q₅₁)(Q₅₂),and —B(Q₅)(Q₅₂), a11l to a13, a21 to a25, a31, a41 to a43, and a51 toa55 are each independently an integer from 1 to 5, R₁₁, R₁₂, R₁₄, R₁₅,R₂₁, R₂₂, and R₂₄ to R₂₉ are each independently selected from: hydrogen,deuterium, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a π electron-depleted nitrogen-free C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a it electron-depleted nitrogen-free monovalent non-aromaticcondensed heteropolycyclic group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenylgroup, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkyl group, a C₃-C₀ cycloalkenyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a πelectron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a π electron-depletednitrogen-free monovalent non-aromatic condensed heteropolycyclic group,each substituted with at least one selected from deuterium, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀ cycloalkyl group, a π electron-depletednitrogen-free C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a π electron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenylgroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a π electron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a πelectron-depleted nitrogen-free monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₅₁)(Q₅₂)(Q₅₃), —N(Q₅₁)(Q₅₂), and —B(Q₅₁)(Q₅₂); and—Si(Q₄₁)(Q₄₂)(Q₄₃), —N(Q₄₁)(Q₄₂), and —B(Q₄₁)(Q₄₂), R₁₃, R₂₃, R₃₁, R₄₁to R₄₃, and R₅₁ to R₅₄ are each independently selected from: a C₃-C₁₀cycloalkyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a πelectron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a π electron-depletednitrogen-free monovalent non-aromatic condensed heteropolycyclic group;a C₃-C₁₀ cycloalkyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a πelectron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a π electron-depletednitrogen-free monovalent non-aromatic condensed heteropolycyclic group,each substituted with at least one selected from deuterium, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀ cycloalkyl group, a π electron-depletednitrogen-free C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a π electron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenylgroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a π electron-depleted nitrogen-free C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a πelectron-depleted nitrogen-free monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₅₁)(Q₅₂)(Q₅₃), —N(Q₅₁)(Q₅₂), and —B(Q₅₁)(Q₅₂); and—Si(Q₄₁)(Q₄₂)(Q₄₃), —N(Q₄₁)(Q₄₂), and —B(Q₄₁)(Q₄₂), R₅₁ and R₅₂ areseparate or are linked to form a saturated or unsaturated ring, and R₅₃and R₅₄ are separate or are linked to form a saturated or unsaturatedring, b31 is an integer from 1 to 10, Q₄₁ to Q₄₃ and Q₅₁ to Q₅₃ are eachindependently selected from hydrogen, deuterium, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, aC₃-C₁₀ cycloalkyl group, a π electron-depleted nitrogen-free C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a πelectron-depleted nitrogen-free C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a π electron-depleted nitrogen-free C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, a itelectron-depleted nitrogen-free monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, and a terphenyl group, inFormulae 61-ET and 71-ET, X₇₁ is O, S, N-[(L₇₄)_(a74)-R₇₄],B-[(L₇₄)_(a74)-R₇₄], P-[(L₇₄)_(a74)-R₇₄], C(R₇₄)(R₇₅), or Si(R₇₄)(R₇₅),A₆₁, A₆₂, and A₇₁ to A₇₄ are each independently a C₅-C₃₀ carbocyclicgroup or a C₂-C₃₀ heterocyclic group, L₆₁ to L₆₃ and L₇₁ to L₇₅ are eachindependently selected from a single bond, a substituted orunsubstituted C₅-C₃₀ carbocyclic group, and a substituted orunsubstituted C₂-C₃₀ heterocyclic group, a61 to a63 and a71 to a75 areeach independently an integer from 1 to 5, R₆₁ to R₆₅ and R₇₁ to R₇₉ areeach independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a substituted or unsubstitutedC₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group,a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂),—B(Q₁)(Q₂), —C(═O)₂(Q₁), —S(═O)₂(Q₁), and —P(═O)(Q₁)(Q₂), in Formula61-ET, i) at least one of A₆₁ and A₆₂ is a π electron-depletednitrogen-containing C₂-C₃₀ heterocyclic group, or ii) at least one ofR₆₁ to R₆₅ is a substituted or unsubstituted π electron-depletednitrogen-containing C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted π electron-depleted nitrogen-containing C₁-C₆₀ heteroarylgroup, and a substituted or unsubstituted π electron-depletednitrogen-containing monovalent non-aromatic condensed heteropolycyclicgroup, in Formula 71-ET, i) at least one of A₇₁ to A₇₄ is a πelectron-depleted nitrogen-containing C₂-C₃₀ heterocyclic group, or ii)at least one of R₇₁ to R₇₃ and R₇₆ to R₇₉ is a substituted orunsubstituted π electron-depleted nitrogen-containing C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted πelectron-depleted nitrogen-containing C₁-C₆₀ heteroaryl group, and asubstituted or unsubstituted π electron-depleted nitrogen-containingmonovalent non-aromatic condensed heteropolycyclic group, at least onesubstituent of the substituted C₅-C₃₀ carbocyclic group, the substitutedC₂-C₃₀ heterocyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group is selected from: deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃),—N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)₂(Q₁₁), —S(═O)₂(Q₁₁), and—P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group; a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂),—B(Q₂₁)(Q₂₂), —C(═O)₂(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)₂(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ toQ₂₃, and Q₃₁ to Q₃₃ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkylgroup, a C₆-C₆₀ aryl group substituted with a C₆-C₆₀ aryl group, aterphenyl group, a C₁-C₆₀ heteroaryl group, a C₁-C₆₀ heteroaryl groupsubstituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroaryl groupsubstituted with a C₆-C₆₀ aryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.
 3. The organic light-emitting device as claimedin claim 2, wherein: A₁₁, A₁₂, and A₂₁ to A₂₄ are each independentlyselected from a benzene group, a naphthalene group, a pyrrole group, acyclopentene group, a furan group, a thiophene group, an indole group,an indene group, a benzofuran group, a benzothiophene group, a carbazolegroup, a fluorene group, a dibenzofuran group, and a dibenzothiophenegroup, A₃₁ is a group of one of the following Formulae A₃₁-1 to A₃₁-38,and A₆₁, A₆₂, and A₇₁ to A₇₄ are each independently selected from abenzene group, a naphthalene group, a pyrrole group, a cyclopentenegroup, a furan group, a thiophene group, an indole group, an indenegroup, a benzofuran group, a benzothiophene group, a carbazole group, afluorene group, a dibenzofuran group, a dibenzothiophene group, apyridine group, a pyrimidine group, a pyrazine group, a pyridazinegroup, a triazine group, a quinoline group, an isoquinoline group, abenzoquinoline group, a benzoisoquinoline group, a quinoxaline group,and a benzoquinoxaline group,


4. The organic light-emitting device as claimed in claim 1, wherein thecompound included in the emission layer and represented by Formula 1A orFormula 1B is a near infrared ray (NIR)-emitting compound having amaximum emission wavelength of about 700 nm or more.
 5. The organiclight-emitting device as claimed in claim 1, wherein: the compoundincluded in the emission layer and represented by Formula 1A or Formula1B is a thermally activated delayed fluorescent (TADF) emitter, and theemission layer emits delayed fluorescence.
 6. The organic light-emittingdevice as claimed in claim 1, wherein the organic layer furtherincludes: a hole transport region between the first electrode and theemission layer; and an electronic transport region between the emissionlayer and the second electrode.
 7. The organic light-emitting device asclaimed in claim 6, wherein: the hole transport region includes a holeinjection layer, a hole transport layer, a buffer layer, an electronblocking layer, or any combination thereof, and the electron transportregion comprises a hole blocking layer, an electron transport layer, anelectron injection layer, or any combination thereof.
 8. The organiclight-emitting device as claimed in claim 6, wherein: the hole transportregion includes a p-dopant, and the p-dopant has a lowest unoccupiedmolecular orbital (LUMO) level of about −3.5 eV or less.
 9. The organiclight-emitting device as claimed in claim 8, wherein the p-dopantincludes a cyano group-containing compound.
 10. The organiclight-emitting device as claimed in claim 6, wherein: the electrontransport region includes a triazole-containing compound or abenzotriazole-containing compound, and the electron transport regionfurther includes an alkali metal, alkaline earth metal, a rare earthmetal, an alkali metal compound, an alkaline earth metal compound, arare earth metal compound, an alkali metal complex, alkaline earth metalcomplex, a rare earth metal complex, or a combination thereof.
 11. Aheterocyclic compound represented by Formula 1A or Formula 1B:

wherein, in Formulae 1A and 1B, ring A₁ is selected from a C₅-C₆₀carbocyclic group and a C₂-C₆₀ heterocyclic group, X₁ is S or Se, L₁ andL₂ are each independently selected from a substituted or unsubstitutedC₅-C₆₀ carbocyclic group and a substituted or unsubstituted C₂-C₆₀heterocyclic group, a1 and a2 are each independently an integer from 0to 5, when a1 is 2, 3, 4, or 5, the 2, 3, 4, or 5 L₁(s) are identical toor different from each other, and when a2 is 2, 3, 4, or 5, the 2, 3, 4,or 5 L₂(s) are identical to or different from each other, when a1 is 0,*-(L₁)_(a1)-*′ is a single bond, and when a2 is 0, *-(L₂)_(a2)-*′ is asingle bond, R₁ and R₂ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazino group, a hydrazonogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₂-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂),—P(═S)(Q₁)(Q₂), —S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂), at least one of R₁and R₂ is an electron donating group, in Formula 1A,(R₁)_(b1)-(L₁)_(a1)-* and (R₂)_(b2)-(L₂)_(a2)-* are not halogen, aphenoxy group, a phenylthio group, an alkylthio group, or an alkoxygroup, b1 and b2 are each independently an integer from 1 to 10, when b1is 2, 3, 4, 5, 6, 7, 8, 9, or 10, the 2, 3, 4, 5, 6, 7, 8, 9, or 10R₁(s) are identical to or different from each other, and when b2 is 2,3, 4, 5, 6, 7, 8, 9, or 10, the 2, 3, 4, 5, 6, 7, 8, 9, or 10 R₂(s) areidentical to or different from each other, c1 and c2 are eachindependently an integer from 1 to 10, at least one substituent of thesubstituted C₅-C₆₀ carbocyclic group, the substituted C₂-C₆₀heterocyclic group, the substituted C₁-C₆₀ alkyl group, the substitutedC₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, thesubstituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted C₁-C₆₀ heteroaryloxy group, thesubstituted monovalent non-aromatic condensed polycyclic group, and thesubstituted monovalent non-aromatic condensed heteropolycyclic group isselected from: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group,a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxygroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃),—N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and—P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group; a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, a terphenyl group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂),—B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃,and Q₃₁ to Q₃₃ are each independently selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₆-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a biphenyl group, and aterphenyl group, and and *′ each indicate a binding site to aneighboring atom.
 12. The heterocyclic compound as claimed in claim 11,wherein ring A₁ is selected from a cyclohexadiene group, adihydronaphthalene group, a dihydroanthracene group, adihydrobenzoanthracene group, a dihydrophenanthrene group, adihydrobenzophenanthrene group, a dihydrotriphenylene group, adihydronaphthacene group, a dihydropyrene group, a dihydrochrysenegroup, a dihydropicene group, and a dihydrobenzopentaphene group. 13.The heterocyclic compound as claimed in claim 11, wherein: the compoundis represented by Formula 1B, and ring A₁ is a group of one of thefollowing Formulae A₁₋₁ to A₁₋₁₂:


14. The heterocyclic compound as claimed in claim 11, wherein L₁ and L₂are each independently selected from: a phenylene group, a pentalenylenegroup, an indenylene group, a naphthylene group, an azulenylene group, aheptalenylene group, an indacenylene group, an acenaphthylene group, afluorenylene group, a spiro-fluorenylene group, a benzofluorenylenegroup, a dibenzofluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, a pentaphenylene group, a hexacenylene group, a pentacenylenegroup, a rubicenylene group, a coronenylene group, an ovalenylene group,a pyrrolylene group, a thiophenylene group, a furanylene group, animidazolylene group, a pyrazolylene group, a thiazolylene group, anisothiazolylene group, an oxazolylene group, an isooxazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an isoindolylene group, an indolylene group, anindazolylene group, a purinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a carbazolylene group, aphenanthridinylene group, an acridinylene group, a phenanthrolinylenegroup, a phenazinylene group, a benzoimidazolylene group, abenzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzooxazolylene group, anisobenzooxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup, a dibenzothiophenylene group, a benzocarbazolylene group, and adibenzocarbazolylene group; and a phenylene group, a pentalenylenegroup, an indenylene group, a naphthylene group, an azulenylene group, aheptalenylene group, an indacenylene group, an acenaphthylene group, afluorenylene group, a spiro-fluorenylene group, a benzofluorenylenegroup, a dibenzofluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, a pentaphenylene group, a hexacenylene group, a pentacenylenegroup, a rubicenylene group, a coronenylene group, an ovalenylene group,a pyrrolylene group, a thiophenylene group, a furanylene group, animidazolylene group, a pyrazolylene group, a thiazolylene group, anisothiazolylene group, an oxazolylene group, an isoxazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an isoindolylene group, an indolylene group, anindazolylene group, a purinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a carbazolylene group, aphenanthridinylene group, an acridinylene group, a phenanthrolinylenegroup, a phenazinylene group, a benzimidazolylene group, abenzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzoxazolylene group, anisobenzoxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup, a dibenzothiophenylene group, a benzocarbazolylene group, and adibenzocarbazolylene group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a pentalenyl group, an indenylgroup, a naphthyl group, an azulenyl group, a heptalenyl group, anindacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a naphthacenyl group, a picenyl group, a perylenyl group, apentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenylgroup, a coronenyl group, an ovalenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thiadiazolyl group, and animidazopyridinyl group.
 15. The heterocyclic compound as claimed inclaim 11, wherein: i) the heterocyclic compound is represented byFormula 1A, a1 and a2 are each independently 0, 1, or 2, and at leastone of a1 and a2 in Formula 1A is not 0; or ii) the heterocycliccompound is represented by Formula 1B, and a1 and a2 are eachindependently 0, 1, or
 2. 16. The heterocyclic compound as claimed inclaim 11, wherein: R₁ and R₂ are each independently selected from:hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₂-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, anda C₁-C₂₀ alkoxy group; a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, aC₂-C₂₀ alkynyl group, and a C₁-C₂₀ alkoxy group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cycloctylgroup, an adamantanyl group, a norbornanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂); a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cycloctyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group; a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cycloctyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amidino group,a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cycloctylgroup, an adamantanyl group, a norbornanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, an imidazopyrimidinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂); and—N(Q₁)(Q₂), —B(Q₁)(Q₂), —P(Q₁)(Q₂), and —C(═O)(Q₁), at least one of R₁and R₂ is an electron donating group, and Q₁ to Q₃ and Q₃₁ to Q₃₃ aredefined the same as those of Formulae 1A and 1B.
 17. The heterocycliccompound as claimed in claim 11, wherein: R₁ and R₂ are eachindependently selected from: hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀alkenyl group, a C₂-C₂₀ alkynyl group, and a C₁-C₂₀ alkoxy group; and agroup represented by one of the following Formulae 5-1 to 5-6, and atleast one of R₁ and R₂ is an electron donating group:

wherein, in Formulae 5-1 to 5-6, K₁ is selected from *—C(R₂₀)(R₃₀)—*′,*—N(R₂₀)—*′, and *—Si(R₂₀)(R₃₀)—*′, R₂₀, R₃₀, R₄₀, and R₅₀ are defiedthe same as R₁ and R₂ of Formulae 1A and 1B, b₄₀ and b₅₀ are eachindependently an integer from 1 to 4, and indicates a binding site to aneighboring atom.
 18. The heterocyclic compound as claimed in claim 11,wherein the compound is represented by Formula 1B, and the compoundrepresented by Formula 1B is represented by one of Formulae 1B-1 to1B-4:

wherein, in Formulae 1B-1 to 1B-4, X₁ is defined the same as that ofFormula 1B, L₁₁ and L₁₂ are defined the same as L₁ and L₂ of Formula 1B,a11 and a12 are defined the same as a1 and a2 of Formula 1B, and R₁₁ andR₁₂ are defined the same as R₁ and R₂ of Formula 1B.
 19. Theheterocyclic compound as claimed in claim 11, wherein: the compound isrepresented by Formula 1B, and the compound represented by Formula 1B isrepresented by one of Formulae 1B-a to 1B-d:

wherein, in Formulae 1B- to 1B-d, L₁₁ and L₁₂ are defined the same as L₁and L₂ of Formula 1B, a11 and a12 are defined the same as a1 and a2 ofFormula 1B, and R₁₁ and R₁₂ are defined the same as R₁ and R₂ of FormulaB.
 20. The heterocyclic compound as claimed in claim 11, wherein thecompound represented by Formula 1A or Formula 1B is one of the followingCompounds 1 to 37: